THE KEEPER'S MAZE by JOE SCHEMBRIE

* * * *

If something can't be what it seems to be, you're overlooking something. Dressed in a rented monk's robe, Joshua Wang emerged from the forest trail. Ahead, beneath the revolving canopy of stars and a two-kilometer arch, torch lights flickered upon the stone walls of a castle. On the field beside the walls, a pair of armored knights faced on mounted chargers, raised lances, and clashed. The throng of tourists gasped as one of the knights tilted off his horse. At the castle drawbridge, guards crossed their pikes.

"Joshua Wang of Raven Space Salvage and Recovery, to see Emil Hamilton."

"I'll see if his Lordship is available," said a guard.

After waiting within the castle courtyard, Joshua was greeted by a young woman bearing a quill, parchments, and a tightly strung bodice.

"Lord Hamilton will receive you," she said, her English accent as deep as the cut of her period dress.

"Prithee come."

He was escorted to a high-raftered chamber adorned with tapestries of knights slaying dragons and one another with equal enthusiasm. It was the only room he'd seen since the docking port that had an undisguised computer.

"Joshua, so grand to meet you!" the lone occupant by the stuffed boar's head bellowed with a cavernous smile. He was costumed as a dead ringer for Henry VIII. "I'm Emil Hamilton." Shaking hands vigorously, he gestured toward the balcony. "What do you think of my little spinning world?" Joshua took a moment to parse the words. Coming from the forest, he had lapsed into thinking he was on an actual planet. In reality, they were over a quarter-billion kilometers from Earth, and the forest, field, and castle were all inside an artificial space habitat--an "asterie," a rotating ring two kilometers in diameter floating in an independent orbit within the Asteroid Belt.

"Scarborough?" Joshua nodded. "Nice."

"A man of few words." Hamilton took a cigar from a jeweled humidor. "Your references mentioned that." They sank into fur-lined chairs before the fireplace and exchanged the small talk typical for the high-context business culture of the Belt. It wasn't long, however, until Hamilton's features lost their joviality.

Hamilton tossed a file folder. "Tell me what you see."

Joshua opened the cover to a photograph of a snow-white horse in rampant pose. From the horse's head protruded a horn, about a meter long, slender and sharp as a rapier.

"A unicorn," Joshua said. If his crew had traveled a megaklick from New Seattle for a joke....

"Plantagenet Line." Hamilton held his cigar to the fireplace and puffed. "Finest breed of unicorn ever to be genetically engineered. It would be a tremendous draw for this resort. It was to be delivered weeks ago, and I want you to pick it up."

"Where is it?"

"Next item."

Joshua flipped to the next sheet in the folder, a photo of an undistinguished crescent among stars.

"An asterie?"

"Daedalus, the zoological development asterie of Daedalus Genetics Limited. It's currently passing within two million kilometers of Scarborough." Hamilton smacked an armrest. "May as well be beyond Jupiter, for all the cooperation I've received!"

"You want Raven to go there and bring you a unicorn."

"Thirty thousand Ceresian credits."

Joshua calmed his heartbeat. "That's a bit much for a short cargo run."

"There's somewhat of a complication. The asterie personnel evacuated and left no forwarding address. You'll board on your own initiative."

"You mean, board without permission. There's a seven-year waiting--"

"Look, I don't want you to salvage the asterie. I just want my unicorn!"

"Still, there are laws--"

"Joshua, you've been in the Belt long enough to know that every asterie is a sovereign entity. My legal point is that they're illegally holding property I've paid for."

"I see."

"I was told you have the requisite skills for cracking abandoned eggs such as this, which is why I'm engaging a salvager rather than a freighter skipper. So is there an insurmountable objection?" Hamilton billowed smoke within inches of Joshua's face. Joshua buried his frown as he studied the photo of the unicorn.

"I can't see us lassoing this thing."

"Let me make it easy. Just go to the main lab and get me the genetic materials that I ordered, so that I can grow my own. A few embryo packs, and you're done."

"What about the keeper? Won't it repel unauthorized boarders?"

"The asterie's sole defense was a sentinel ship. The personnel departed aboard it. The asterie is now toothless. And the keeper is one of those doddering traditional types that can't hurt a fly. Plus, it's daft."

"Daft?"

Hamilton chuckled. "Issuing threats about a maze or some such nonsense."

"A maze?"

"I don't know anything beyond that. Contact it yourself."

Outside and below, metal crashed with metal. A thousand voices gasped. Joshua riffled the folder's pages. And he thought: thirty thousand credits.

"We'll need ten percent up front. For fuel and mission consumables."

"You're accepting?"

"I'll have to consult my crew."

* * * *

At the mooring position fifty kilometers from Scarborough, the control room camera swiveled to greet Raven's returning captain and the voice of the ship's computer emanated from a speaker grid: "Welcome home, Joshua."

"Thank you, Hermes." Garbed once more in twenty-first-century tee shirt and slacks, Joshua slipped into the navigator-pilot's chair. "All's well, I trust."

"All ship's systems are well," Hermes replied. "However, Lucas has stated that he is not well." Both Ann Striker and Lucas Chulaski, Joshua's fellow crewmates aboard Raven, were present in the control room. Ann was pressing a cold compress to Lucas' head. Lucas half-opened an eye and moaned.

"My anti-addiction implant," Lucas said. "It's too sensitive. We go to a tavern, I pour a flagon of mead and toast the green, green, lice-infested hills of Earth--and pow! A hangover with just one sip!"

"See what I got?" Ann said. "Reena will love this!" She unribboned a box and unwrapped a crystalline figurine of a unicorn.

"Gift shop was bursting with unicorns," Lucas said. "Glass, gold, chocolate. It's unicorn mania over there."

"Yes," Joshua said. "There's a reason."

He briefed them.

Lucas massaged his temples. "Joshua, is there an honest asterie developer in the Belt? Especially this guy. The rumor over there is that he strong-armed the creator of Scarborough to sell."

"I know it's only a themeworld," Ann said. "But I wonder about a person who has flunkies calling him

'lord.'"

Lucas nodded. "Or baron or whatever. That whole serfdom scene."

"On the other hand," Ann continued, "I'd love to see a live unicorn!"

"What we need to see," Joshua said, "is the mythical, black-bottomed income statement. Which is why we're even considering a job like this."

While Joshua concocted their ritual bull-session espressos, a subdued Lucas linked to Asternet and contacted Ceres Legal, whose AI counsel sifted through the interlocking maze of treaties and concordats that served the Asteroid Belt in lieu of a central government.

"Ninety-five percent precedent that arbitrage courts will find in our favor should we board without permission," Lucas read from the screen.

"Forced entry still bothers me," Ann said.

"This operation will be nonviolent and nondestructive," Joshua replied. "If we have to do more than drill a lock, we'll withdraw."

"Aye, Captain," Lucas said. "About this maze business--"

"It's time we went to the source."

Joshua held the coordinates sheet to the control room camera. Hermes traded protocols over the standard one-hundred-gigahertz tightbeam communications link, establishing plain-text as the baseline message format.

CALLING ASTERIE DAEDALUS, Lucas typed. THIS IS SPACESHIP Raven. REQUEST

CONTACT WITH YOUR MASTER.

Lucas's screen flashed the response, thirteen seconds of lightlag later: SPACESHIP Raven, THIS IS

THE KEEPER OF DAEDALUS. ASTERIE PERSONEL ARE NOT AVAILABLE AT THIS TIME.

"Ask what happened to them," Joshua said.

Lucas typed. The keeper responded: PERSONEL ARE NOT AVAILABLE AT THIS TIME.

"Request permission to board and lend assistance."

PERMISSION TO BOARD IS DENIED.

"If we attempt to board, do you threaten harm?"

I HAVE NO WEAPONS. I AM PROGRAMMED NOT TO HARM. HOWEVER, THOSE WHO

ENTER THE MAZE WILL NEVER ESCAPE.

"Tell us about the maze."

NO FURTHER INFORMATION WILL BE PROVIDED. THOSE WHO ENTER THE MAZE

WILL NEVER ESCAPE.

"Lucas," Joshua said. "You think the keeper's on the level?"

"Keeper artificial intelligences are programmed to maintain the stability of asterie environments," Lucas replied. "Usually, they're specifically programmed not to practice deception. And if it could lie, why not threaten to shoot us?"

"So what is this maze?" Ann asked.

"Well," Lucas said, "the thought processes of keeper-type AIs are concrete, not metaphorical. So, presumably, it's a physical maze."

"It's actually rearranged its interior?"

"Unusual, but conceivable. The maintenance robots could do the remodeling."

"Lucas, it makes no sense! Aren't computers supposed to be logical?"

"Ann, being logical is different than making sense. Here's how I think it works. To start, it's an older, tradition-minded keeper, with inviolable ethical parameters--"

"Asimov's Three Laws," said Joshua, who liked to read historical science fiction.

"Uh, yes," Lucas said. "At any rate, its ethics are carved, so to speak, into the bedrock of its operating system. So it can't harm us, by action or inaction."

"And the maze?" Ann asked.

"Perhaps, while they were evacuating, the asterie personnel ordered the keeper to protect the asterie from intruders at all costs. So the keeper had to develop a non-lethal way to comply."

"A maze," Ann said. "I'll bet it's really a trap."

"Getting trapped aboard a deserted asterie could be lethal," Joshua said. "Which violates its ethical programming. Let's point that out."

The delay was longer than thirteen seconds.

TO ANSWER YOUR OBJECTION, THE MAZE IS NOT A TRAP. A WAY OF EXCAPE IS

ALWAYS AVAILABLE. HOWEVER, IT IS IMPOSSIBLE TO ESCAPE FROM THE MAZE.

Pause. NO FURTHER INFORMATION WILL BE PROVIDED.

"If it was human," Ann said, "it would know it's only making us curious."

"I realize this is the Belt and anything can happen," Lucas said. "But who's afraid of a maze?" They discussed a few minutes more, then drained their espressos and voted.

* * * *

Two weeks and two million kilometers later, the ship collapsed its plasma bubble and, with milligee deceleration, parked fifty kilometers from the asterie.

Daedalus was an unburnished ball with no major protrusions or cuts save a hangar at one end of the spin axis and a rocket exhaust nozzle at the other. The rim rotation calculated to half a gee simulated gravity on the five-hundred-meter equatorial radius.

They observed the telescopic view on the control room's main screen.

"We call asteries 'eggs,'" Ann said. "But this actually looks like one."

"A common design for a space habitat," Joshua said. "Use a solar mirror to heat a ball of metal to molten, inflate like a balloon, cool to solid. Very simple, very cheap."

"Very claustrophobic," Ann said.

" Raven's hull sensors are tasting radioactive isotopes," Lucas said, reading a chart-laden side display.

"Traces of krypton-85 and iodine-131."

"Typical of a fission reactor," Joshua said.

"How do you know that?"

"I was an engineering mate, long ago. Some days I wish I hadn't made the career change." Joshua stared at a bar graph on Lucas's screen. "The reactor must have been operating recently if the iodine-131 is still significant. The half-life is only eight days."

"The reactor isn't being used for propulsion," Ann said. "The asterie hasn't moved in two weeks."

"It's being used for internal power requirements," Joshua said. He nodded to the image on the screen.

"You'll notice, no solar mirrors or panels."

"A reactor presents a smaller radar cross-section," Lucas said.

"A nuke is a lot more expensive than solar arrays," Ann said. "They're going out of their way to keep a low profile."

"Gazing as I am upon this orb of mystery," Lucas said, "I once more ponder our client's true motives."

"The answers are inside," Joshua said. "If there are any."

* * * *

They dispatched Hermes Junior and watched its telemetry on the control room main screen. The robot surveyed the asterie's shell at one hundred meters. The camera relayed images of dull, smooth metal, and of tiny, highly radioactive vent ports. It soon became apparent that the only humanly or robotly possible entry was through the hangar.

Synchronizing with the hangar rotation, the barrel-like scout robot alighted on the deck, and rolled past the vacant docking berths to the main personnel airlock. The opening mechanism was a single button. Junior erected a transmission repeater. Elevating an appendage, it pressed the airlock button. The door slid open. The robot cycled inside.

"Too easy," Joshua said quietly. "For thirty thousand credits, that is."

"Normal pressure and oxygen ratio," Ann said, scanning her data-feed screen. "Radiation in the safe zone, biofilters clean. Temperature sixteen centigrade--sweater-wearing weather." Lucas cocked an eyebrow. "How does the unicorn get the sweater over its head?" Ann grinned and swatted his shoulder.

"Carry on, Junior," Joshua said.

"Right-oh, Joshua," Hermes Junior said.

Unspooling a fiber optics cable after itself, the robot rolled deeper within the asterie. Its camera eyes relayed empty passages and barren compartments. Socks and shirts lay scattered haphazardly on the cabin floors.

"They were in a hurry to leave," Lucas said.

"What are those?" Ann demanded.

Lucas flipped on Junior's head lamp. Inside a dark room, a dozen pairs of yellow dots gleamed from floor level. Brown furry shapes the size of shoes scurried into the shadows. Over the speakers came squeaks and squeals.

"Rats!" Ann said.

"We've seen rats in abandoned asteries before," Lucas replied.

"These look different. Can you get closer?"

Lucas drove Junior over the threshold, but just then a lamp crashed from a desktop, missing the robot by centimeters.

"We're not here for rats," Joshua said.

Junior exited the cabin and continued down the passage. A rat waddled across an intersection, and more eyes blinked from darkened rooms.

"A regular infestation," Ann said.

"In a way it's comforting," Lucas said.

They stared at him.

"Regarding the maze," he said. "If the rats solved the maze, how hard can it be?" Junior passed an elevator and, mindful of its trailing cable, trundled down a ramp instead. Then the walls changed, becoming uniform and smooth. The robot entered room after room filled with containers. Most of the containers were refrigerator and freezer units, plugged into wall outlets.

"They carry a lot of cargo," Lucas said.

"A zoological asterie would," Ann said. "As it orbits through the Belt, it passes asteries in neighboring orbits, and merchandise is transferred back and forth."

"Like a mobile distribution center," Joshua said. "Or flying warehouse." With Joshua wearing the teleoperations glove, Junior undid latches, twisted handles, and pushed open sliding doors. Each doorway led to another compartment, without intervening passages. Despite the sameness of the walls, the compartments followed a seemingly random geometry and were seldom the same size and shape.

"Maybe this is the maze," Ann said. "I'm confused already!"

"Hermes will remember the way out," Lucas said. "But how are we going to find the lab? The compartments aren't labeled. How did the people who worked here find their way around?" Joshua said: "The keeper must have directed--"

"Whoa!" Lucas said.

The wall in front of Junior bore coin-sized punctures, set in a curving line.

"Automatic rifle fire," Joshua said.

Lucas panned the camera. The other walls were similarly strafed.

"An all-out battle," Lucas said. "But why? Pirates? Mutiny?"

"Hey, guys," Ann said. "Does it seem like there's more rats?" Lucas panned again. From each corner, behind every container, a pair of beady yellow eyes blinked. Joshua had seen plenty of rats aboard derelicts. Yet these were different. They were larger, bulkier, and their fixed stares prickled his neck hairs.

Just then, the screen went blank. Lucas barked at the control room camera: "Hermes, report!"

"Scout telemetry lost," Hermes replied. "Comm cable break indicated." Joshua stroked his chin. "Let's contact the keeper."

"I'll get voice this time," Lucas said.

A moment of frenetic typing later, and a male-sounding voice said over the control room speakers, "This is the keeper of Daedalus."

The voice was calm, almost deferential. Joshua realized he had assumed from the capital letters of the plain-text transmission that the keeper had been shouting.

"Keeper," Joshua said. "I am Joshua. I am captain of the spaceship Raven."

"Hello, Joshua."

"Keeper, what have you done to our scout robot?"

"I have not harmed your property, Joshua."

"Then what happened to it?"

"Nothing has happened to it, Joshua. It is unharmed."

"Then what caused its communications cable to break?"

"The cable was broken by the maze."

"The maze? How?"

"No further information will be provided. However, there is no escape from--" Joshua disconnected. He zoomed the telescopic view on the main screen. For a long moment, he gazed at the asterie's revolving, uninformative shell.

"Our turn now," he said.

* * * *

"Nonviolent and nondestructive," Ann said, watching Joshua load a snub-nosed automatic rifle into each of their personal carrybags.

"We won't start trouble," Joshua replied.

"Those bullet holes." Ann shuddered. "I'm a single mom! If I didn't need the money so badly--"

"Are you staying here?"

A long pause. "No. Of course not."

Lucas opened the explosives locker and loaded his carrybag with his hand-made charge packs.

"Plan on blasting your way through the maze?" Ann asked.

"It's one solution," Lucas replied. From a strongbox within the locker, he removed several candy bars in red-and-white foil wrappers. Meeting their gazes, he said, "Hey, supposing we do get trapped!" Once fully suited, they boarded the skiff, broke from the de-spun ship, and flitted toward the asterie.

"Joshua," Hermes said over the radio. "The keeper of Daedalus is calling for you."

"Something about no escape from the maze?"

"Yes, Joshua."

"Let me know if it has something else to say."

Minutes of crossing open space, and the skiff alighted in the hangar. They dismounted and, with Joshua leading in a show of decisiveness that he didn't quite feel, they cycled through the airlock. The inner door slid open. Their helmet lamp beams revealed an unlit compartment whose rows of lockers and shelves burgeoned with space suits and helmets and other outside-the-hull equipment.

"Pretty pricey stuff to abandon," Lucas said. "And in good condition. Too bad we're not here to salvage. Our financial problems would be solved with this one room."

"Keep your suits on," Joshua said. "They may have evacuated because of a plague."

"I doubt it," Ann said. "If they were doing macroscopic genetic engineering here, they wouldn't mess with viruses. It would endanger breeding stocks."

"I hope you're right, Ann."

Lucas scrunched his mouth at his computer tablet, which was connected to a Geiger-MÃ¼ller-style radiation detector on his belt. "Radiation is registering safe levels. No alpha or beta, very low gamma."

"Keep monitoring," Joshua said. "A reactor problem is another possible reason for evacuation." Lucas attached his spool of fiber optics cable to the same repeater that Junior had erected on the interior side of the airlock. He unspooled his cable behind them as they progressed down the passage, their helmet lamp beams bobbing spots upon the walls.

They managed only a few steps when the overhead lights gleamed on.

"It's making us welcome," Ann said. "Even though it wants us to leave."

"Don't human hosts show courtesy toward their unwanted guests?" Lucas asked. Ahead lay a brightly illuminated, spotlessly clean ship's corridor. Joshua listened with his suit's external microphones at maximum. The lights hummed and the ventilators purred. Far off came a creak.

"Let's go," he said.

Switching off their helmet lamps, they followed Junior's cable. In every compartment, eyes blinked from behind the storage containers.

"Joshua," Hermes announced. "The keeper is saying something else."

"Pipe it in."

The keeper's words bounced from the asterie to Raven, to the antennas and repeaters at the hangar airlock, down the fiber optics cable in the passages to the transmitter that Lucas carried, and into Joshua's space suit earphones.

"Joshua," the keeper said in its always-calm voice. "I request that you not deface the property of Daedalus Genetics, LTD."

"We're not defacing anything," Joshua said.

"There is a person in your party who is defacing the walls." Joshua looked around. Ann stood by the portal, lipstick dispenser in hand. A red wedge was scrawled on the adjacent wall.

"I got the idea from a movie," Ann said. "You want me to stop?" Lucas wiggled his tablet. "I'm video-logging our journey. And anyway, all we have to do is follow the cable out."

"Keeper," Joshua said. "The marks will wipe off." To Ann: "Keep doing it. I like having back-up procedures."

They continued down ramps and through passages, tracking Junior's cable. Joshua raised his eyes to the ceiling. In every compartment, he saw the same arrangement of light fixtures, ventilator grids--and little black hemispheres.

Cameras, he thought. It's watching.

Lucas viewed his tablet. "This next room is where Junior's cable broke." Joshua halted at the portal. Unzipping his carrybag, he removed his rifle and slung it over his shoulder. Ann and Lucas imitated. Squeezing the rifle grip, breath heavy and heart pounding, Joshua crept to the frame and peered through.

On the floor, between container pallets and rat eyes, Junior's cable extended to the opposite wall--and terminated.

Lucas examined the cable end. "Look how frayed this is."

"Rat chews?" Ann asked.

"Looks like it was severed by something blunt. And powerful." Ann did a full turn. "Where does the cable continue?"

A freezer unit occupied the center of the compartment. An electrical cord trailed from the side. Its plug lay on the floor. Joshua looked for an outlet. There wasn't any nearby. He pointed his laser-beam temperature sensor at the freezer unit's door seal.

"This freezer was running until recently," he said. "Then it was unplugged."

"By who?" Lucas asked.

"That is the question. Keeper, are you still on the line?"

"On what line, Joshua?"

"Never mind. Got a question for you. Besides us in this room, are there any other humans aboard this asterie?"

"No, Joshua. They have all been evacuated."

"What about robots?"

"My robots have been evacuated. There is also your robot. There are also five unidentified robots which entered the maze unauthorized thirty-seven days ago."

"Those sound like Hamilton's doing," Joshua said to Lewis and Ann. To the keeper: "The unidentified robots. What is their status?"

"They have not moved in thirty days. Analysis indicates loss of battery power."

"So, Keeper," Lucas said. "Who unplugged this freezer?"

"No further information will be provided," the keeper replied.

"You know, Keeper," Lucas said, "that refrain is starting to annoy." The keeper remained silent.

"Maybe the rats unplugged the freezer," Ann said. "I realize that sounds like I'm obsessing over them--but they do have the ability."

"I can't see their motive," Joshua replied.

Ann crossed her arms. "Well, do we have a search plan? I mean, this place is creeping me out--the evacuation, the rats, the bullets. I'd like to get done as soon as possible."

"Hermes calculated there's over half a billion cubic meters here," Lucas said. "If we just bumble around, it'll take forever."

Joshua thought for a moment. The direct approach, he decided, was often best.

"Keeper."

"Yes, Joshua."

"You're watching us, aren't you?"

"Yes, Joshua. I have been ordered to monitor intruders. I regret the compromise of your privacy."

"That's all right. So you know where we are. Keeper, I have a request."

"Yes, Joshua."

"Can you guide us to the main lab?"

"No, Joshua. I have been ordered not to direct intruders there." Lucas smiled. "Guess that was worth a try."

Joshua thought again. People rushing to evacuate, forgetting that computers are often literal-minded when it comes to interpreting commands-"Keeper. Can you guide us to the room in front of the main lab?"

"Yes, Joshua."

"Keeper, guide us to the room in front of the main lab."

"Yes, Joshua. Please go through the door on your right."

Lucas dropped his jaw. "Joshua, next election for captain--you've got my vote!" Joshua released the rifle grip. Mindful of the overhead camera and the possibility that the telemetry might someday be viewed by a court-of-arbitrage jury, he stuffed his weapon back into his carrybag.

"Okay. Let's head--"

He saw Lucas frowning at the wall where the cable had broken. Lucas ran his gloves along the surface, and pounded.

"What's up?" Joshua asked.

"According to Junior's telemetry," Lucas said, "there should be a doorway here."

"Portal," Joshua said, reflexively giving the standard space-freighter terminology. "I don't see one."

"Well, I thought I reviewed the video correctly." Lucas shrugged. "Maybe I made a mistake. Been known to happen."

Joshua found he couldn't let it go that easily.

* * * *

To Joshua, the main lab was merely boxes of lights and switches juxtaposed with liquid-filled tanks and interconnecting tubes. Ann's eyes were aglow.

"I wish we could salvage this just to play with it!" she said. "This is the best gene-editing equipment I've seen in the Belt."

Batting Lucas's hands away from a workstation keyboard, Joshua inspected a wall with shelves of transparent jars like inverted space suit helmets. The bowl interiors seemed coated with sea salt and slime.

"Artificial wombs," Ann said. "A little small for unicorns, though."

"Guys!" Lucas called.

They joined him at the other end of the lab. From a second-story perch, a picture window overlooked a chamber larger than a terrestrial city's sports stadium.

Beneath the light fixtures that dangled scores of meters overhead stretched a vista of hundreds of meters. The chamber contained a forest of gnarled, barren trees, prickling a landscape of hillocks and gullies. Clearings of yellowing grass broke the treelines.

The largest clearing, on the right, had a dried lake bed, orange with rust. The lake bed abutted the only wall visible from the laboratory window. The curvature of the asterie hid the other ends of the forest from their sight.

"An ecosystem module," Ann said. "This must be where they tended the grown specimens."

"It hasn't been watered for a while," Lucas said.

"Gloomy, too," Ann said. "Half the lights are burnt out."

"Let's find the storage unit," Joshua said.

The main room of the lab diverged into short hallways lined with doors. Joshua read the door plaques.

"Fifty-four alpha. This is it."

The door was locked, the first time they'd encountered a locked door since coming aboard. A brief whir of Joshua's drill annihilated the lock mechanism. Joshua entered the storage unit and, cutting the refrigerator padlocks, compared the serial number on Hamilton's purchase order with the labels on the embryo packs. He immediately frowned.

"There are two different serial numbers here," he said.

They withdrew a finger-sized bottle from each pack. Ann inserted the needle of her DNA comparator into both.

"This first one registers as genus Equus--which is right for horses," she said. "I wish I could be more specific, but unicorn DNA is proprietary, so it's not in my comparator's genome library."

"How about the other pack?" Joshua asked.

"Definitely not Equus ... wow, whatever it is, it's been heavily modified. But my educated guess would be

... order Rodentia."

" Rodentia," Lucas said. "Rodents?"

"Uh-huh. Maybe they were experimenting with pest control. Goodness knows they need it."

"So we take the horsies, leave the mousies?" Lucas asked.

"Not so simple," Joshua said. He stabbed at the hard copy of the purchase order, which he had carried from Scarborough. "The Equus number isn't listed. The Rodentia number is."

"Their inventory data base is probably confused," Lucas said. "If you'll let me hack their system--"

"No. The easiest solution is to take both. We'll return parcel-post whichever Hamilton doesn't want." They wrapped the embryo packs in insulation and stuffed their carrybags to overflowing.

"Lot of baby unicorns here," Lucas said. "Is our friendly and trustworthy client planning to raise a cavalry regiment?"

"All Belters are crazy," Ann said. "Look at us."

Joshua frowned at the serial numbers on the packs, then slung his carrybag's strap over his shoulder, staggered to the door, and motioned outward.

"We've got what we came for. Let's go see stars again."

"About time," Ann said. "All this talk about mazes has me scared we'll run into a minotaur."

"That could happen in a genetic engineering facility," Lucas said.

"Lucas, honey--please shut up!"

Joshua crowded out fears of minotaurs with a daydream of their traditional post-mission espressos-and-cookies in the coziness of Raven's control room. He was halfway to the lab exit when Ann cried out. She was staring through the window toward the clearing. Not more than a few meters distant inside the ecosystem module, a snow-white horse munched on the sparse grass.

The horse had a mane tangled with elflocks. Its eyes were wide and liquid. Upon its head projected a golden-hued horn like a jousting lance in quarter-scale.

It happened too fast for Joshua to stop her.

Shedding her carrybag, Ann descended the stairwell, flung open the door, and entered the ecosystem module. With more caution, the men followed.

The unicorn perked, neighed, and trotted to the clearing edge, as far as it could go without entering the woods. It surveyed the three of them, swishing its tail and grunting. Its head bobbed and the horn flicked like a swordsman's parry.

"She's so pretty!" Ann said, after briefly stooping to determine sex.

"A little on the thin side," Lucas said. "Little ragged, too."

"Dehydration." Ann sighed. "This whole place is run down. There's hardly any grazing. Poor thing!"

"Ann," Joshua said. "It's an untamed creature, we have no ability to capture it. Didn't you say you wanted to leave?"

The unicorn made a noise like, " Ruh-uhhhhh!"

Ann grabbed Lucas's carrybag. She extracted a fistful of red-and-white wrappers.

"Hey!" Lucas cried. "My stash!"

Peeling off a wrapper, Ann held out a chocolate bar and approached the unicorn, step and halt, step and halt. The creature grunted and stamped, like a bull preparing to charge. Watching the horn tip's circles, Joshua slowly reached into his carrybag.

"Don't you dare, Joshua!" Ann said. "My suit will protect me from the horn." Joshua curled his finger around the trigger just the same.

Midway across the clearing, Ann stopped. The unicorn examined the candy with both eyes and flaring nostrils. It trotted forward and its teeth pried the bar from Ann's fingers. With a gulp, the bar vanished. Ann unwrapped a second bar.

As the unicorn munched, Ann delicately slipped alongside, whispering gently. The creature grunted and bobbed its head, as if in comprehension. The horn stayed pointed away from Ann.

"'Constance,'" Ann said lightly. "My daughter Reena has a stuffed unicorn named Constance. That's a good name for you." She stroked the mane. "Your hair is so soft, Constance! And you're so well-behaved!"

"She's a moocher, that's what she is," Lucas said, as Constance the unicorn nibbled on the chunks of a third bar. Lucas turned to Joshua. "Perhaps we should discuss who'll clean up after this charming beast, assuming we take her aboard Raven."

"I'll do it," Ann said. "Horse lovers run in my family. Besides, handling a horse will be no trouble after cleaning up after you two!"

Lucas placed his hands on his hips. "Ann, you are being unfair. Accurate, irrefutable--but also unfair." Suddenly, the unicorn's ears twitched. Her eyes widened still more. She bolted into the woods, a streak of white swallowed into the gloom.

"Something spooked her," Lucas said. "But I don't see or hear any--" Ann stared at the swaying branches--then plunged after.

"Ann!" Lucas shouted.

Joshua raced after Lucas, who chased after Ann. Overhead, the branches blocked the faltering illumination. Around Joshua, shadows merged into thickets of black. Animated stickers whipped his space suit and snapped at his helmet.

In the murk of the forest he thought he glimpsed a spider web large as a man, a spider big as a bowling ball. He saw the bones of a half-eaten pterodactyl carcass. He saw hulking silhouettes that had to be his imagination.

He came to a fork in the trail. On the left, a branch swayed. He went left. Then he broke into a clearing. Ann and Lucas were frozen, gaping at the gully below. Since it took him a moment to accept what he was seeing, he froze too.

Row upon row of huts ran parallel to the dried stream bed at the bottom. The huts had walls of sticks and stones, roofs of straw, and bare apertures for windows and doors.

The tallest roof towered no higher than Joshua's knee cap.

"Does this mean what I think it does?" Lucas asked.

"Back to the lab," Joshua said. " Now."

Through the windows, furry heads peeped beady eyes.

* * * *

Joshua swung open the lab door and ushered the others in. He sprang after them and slammed the door. Breathless, he clambered up the steps.

Beyond the window, on the far side of the clearing, the tall grass shook. Joshua expected a wave of brown fur to wash out. Instead, he saw a flood of leaves.

The rats wore caps of leaves, and around their waists, cinched by strands of grass, were jackets of leaves. Their mock uniforms blended with the dead leaves matting the ground. Maneuvering into the clearing, the rats formed into squares of hundreds. At the forefront of each square pranced a larger-than-average rat attempting to lumber upright while waving a sharp stick. Joshua saw petals of marigold gracing the shoulders of the uniforms of the leader rats. Next to each leader, a pair of smaller rats held ceilingward a long branch with three leaves skewered. Joshua thought of epaulettes and regimental colors.

"It's like a miniature army," Lucas said. "How do they know to do that?"

"It's taken decades to program their instincts into imitating human military tactics," Ann said. "But that's all it is. Instinct and imitation."

"Like bees and their hive behavior coupled with monkey-see-monkey-do?"

"Yes. Instinct and imitation. That's all it is. Despite the name, intellirats are more clever than intelligent."

"You can only genetically engineer so much strategy into brains the size of walnuts," Joshua said. He wondered how much military strategy that was. Likely, he thought, he had only a peanut's worth himself. The squealing rattled the lab window. The multitude of cries were regular and synchronized, chants led by the officer rats and directed toward the humans.

"Why are they so furious?" Lucas asked.

"We violated their territory," Ann said.

"Let's stay out of sight," Joshua said. He headed for the exit. "We have what we need, let's--" Ann stood by the window, glaring. "We're abandoning Constance? In there, with them?"

"We--we can't--we have to--" Joshua couldn't form a complete sentence under her scrutiny. Then he noticed Lucas.

Lucas stared at the flashing screen of his computer tablet, clutched in both hands with far more of a grip than required in a point five geefield.

"Something wrong, Lucas?" Joshua asked.

"Radiation detector," Lucas said. "A significant increase in iodine-131." Joshua and Ann traded glances.

"How much is the gamma?" Ann asked.

"Point three millirem per hour. Is that harmful?"

"Not if we're leaving right away."

"It shouldn't be anything at all," Joshua said.

He examined the history graphs for counter-and-average-MeV.

After a period of time, Ann said: "The reactor is running high, isn't it?"

"At fever--since about forty-five minutes ago," Joshua said. "Maybe Hermes can tell us what's happening." Hefting the fiber optics cable spool, Joshua flipped the transmitter switch. "Hermes, you there?"

Hermes wasn't. After a few calls of wasted breath, Joshua glanced at the ceiling grids.

"Keeper," he shouted through his helmet glass. "Can you hear me?"

"Yes, Joshua," said the voice from a circular grid.

Joshua adjusted his helmet external-microphone volume.

"What's the status of your reactor plant?"

"I have placed my primary reactor at maximum power and am disengaging all safety features," the keeper said, in a voice whose dispassion matched that of a human describing how to bleach stains from laundry.

"I am preparing to pump ice-cold water into the core. This will result in a rapid and extreme temperature transient that will stimulate a high flux of thermal neutrons, leading to explosive meltdown. The meltdown event will fulfill my directive to self-destruct upon intruder penetration of the main laboratory." There was a long silence.

"It's the intellirats, isn't it?" Ann said. "We found out about the intellirats."

"Yeah, Daedalus Genetics has to destroy the evidence now." Lucas shook his head. "If there's anything that'll summon the navies of a dozen asterie alliances to your doorstep, it's breeding intellirats."

"Keeper!" Joshua shouted. "Return your reactor to normal operation!"

"I am sorry, Joshua," the keeper replied. "You do not have countermand authorization." Joshua opened his mouth to shout again, but Lucas interrupted: "Keeper, when will meltdown occur?"

"There is a point nine nine confidence interval between seventy-five and eighty-one minutes," the keeper replied. "I regret that unknown reactor tolerances prevent a more specific answer." Joshua adjusted his watch. "Lucas, does that give us enough time to leave?" Lucas skimmed the video log of their inward journey. "If we don't delay." He looked at Ann. Ann turned from the woods. Her face had no tears, just a hollow glaze.

"Let's go," she snapped.

* * * *

Exiting the lab, they followed the cable through portals, past pallets. Joshua's legs increased speed unconsciously. And so, head bowed, he almost slammed into a wall.

He picked up the frayed cable end. "Blunt cut. Like the other one!" Lucas compared his computer tablet screen to the wall. "According to the video, there should be a door--a portal--here!"

They slapped the bare surface. It didn't make a portal appear, not even a crack. With his boot, Lucas nudged another disconnected electrical plug. "Who's doing this? An energy-conscious minotaur?"

"The keeper may have lied about not having robots," Joshua said.

"Joshua, I told you, the keeper can't lie!"

"Lucas, there's the cable and there's the wall. Either we walked through the wall or this cable has been rerouted."

"Well, is the keeper editing my video log, too?"

"It's got to be the right place, Joshua," Ann said. She pointed to the lipstick mark on the portal frame. Joshua sighed. "We don't have time for this." Conscious of his flushed cheeks, he tucked his irritation away. He keyed in his laser gyro, determining the direction of the hangar. "We need to go through this wall."

Lucas blinked. "You mean, blast through it?"

"I, for one, am not worried about lawsuits anymore," Ann said. Lucas taped the explosive charge in place. They hid in the adjoining room. Lucas tapped his computer tablet screen. The portal flashed and the boom shook the walls. Debris flew past. They poured back into the other room. A hole smoldered in the center of the wall.

Joshua strode toward it, but not fast enough.

The wall moved back. The ceiling parted. Down came a new wall, joining with the floor and adjacent walls. The ceiling closed up.

They faced a bare, smooth wall. If they had delayed reentry into the room, it would have seemed as if the detonation had been without effect.

Gingerly approaching, Lucas examined the new wall, rapping his knuckles on the edges and corners.

"Electromagnetic induction coils," he murmured. "That's how it moves so fast."

"But why?" Ann demanded. "I mean, why would an asterie have walls that move?" Being mesmerized, Joshua took a moment before he could speak.

"Ann, you agreed Daedalus was like a flying warehouse, drifting from one customer--and supplier-asterie to another as it orbits through the Belt. Well, to maximize storage efficiency, it has to reconfigure itself to cargo allocation requirements, which are constantly changing."

Lucas nodded. "You're saying the keeper automatically remodels its interior to adapt to its cargo?" Ann sighed heavily. "Only in the Belt!"

"Not just here," Joshua said. "I've heard about this on Earth, too. Commercial airlines have been doing it for over a century. In the daytime, a jet will fly with passenger seats. At night, the seats are removed and pallet tracks are installed, to haul freight. It's so routine, they don't even use robots anymore. The jet reconfigures itself."

"A dynamic maze!" Lucas said, his eyes lighting. "That must be the key, how the keeper rationalizes its actions! It always provides a way of escape, so it can justify to itself that it's not actually trapping us. But the escape route constantly shifts in response to our movements, so that--"

"So that we're always going the wrong way." Joshua raised his eyes to the ceiling bubble. "Keeper! Can you take us to the room that is next to the hangar?"

The keeper's voice was prompt and smooth: "I'm sorry, Joshua. That would facilitate your escape."

"It's learned that trick," Lucas said.

"Keeper," Joshua said. "Do you realize that the meltdown will kill us if we cannot escape in time?"

"In regard to the meltdown event," the keeper replied, "while normally my ethical parameters would require me to release you in the face of imminent danger, my self-destruct directives are an exception and must exclude any consideration on my part with regard to your personal safety."

"Keeper, that's not logical!"

"I believe you are incorrect, Joshua. My programming instructions are explicit. Human Life Protection overrides all priorities except Self-Destruct. Self-Destruct is independent of Human Life Protection." Joshua felt his face grow red, his stomach churn. He also felt a need to punch something.

" Keeper--"

"Joshua," Lucas said quietly. "Don't argue with the computer." Joshua unballed his fists and slowed his breathing. "All right. Lucas, can we blast our way back to the hangar?"

"Not if the keeper throws a hundred walls in our way. Even just ten. I only have nine more charges." For an instant, it got to be too much. Swirling into a maelstrom of worries, Joshua bowed his head and closed his eyes.

"I'm sorry," he said, covering his temples with his hand. "I worked on freighters, I should have thought of reconfigurable compartmenting before this."

Feeling a palm on each shoulder, he opened his eyes. Lucas and Ann smiled at him. Small smiles ... but enough.

And by then, he remembered ... the rust.

"Let's go back to the ecosystem module," he said.

"The rat's nest?" Lucas asked.

"I hope you can think of a better idea on the way. Mine isn't that good."

* * * *

Inside the lab, Joshua pointed through the window at the orange bottom of the dried lake bed near the right-side wall, about a hundred and fifty meters distant. There were no rats in the foreground, no unicorn anywhere.

"Because of the heaviness of its biomass," Joshua said, "the ecosystem module is built right on top of the inner surface of the asterie's outer shell, with no levels underneath. Right?"

"Gotcha," Lucas said. "You want to blast a hole through the shell."

"The lake bed's rust must be from the steel shell. That's where we'll do it."

"Then we jump through the hole?" Ann said. "That's your plan?"

"The rim rotation is fifty meters per second," Joshua said. "That'll throw us clear of the meltdown. Hermes will have the skiff pick us up."

"Joshua," Lucas said. "I once saw this documentary on World War II battleships. Their plating was two feet thick. The average asterie's shell is three times that."

"I'm not optimistic, either."

Joshua descended the steps and opened the door. His earphones filled with the shush of a breeze from distant, hidden ventilator fans. With suit external microphones at maximum sensitivity, he listened toward the woods. He heard something like the caw of a crow on steroids. There were no squeaks or squeals. They gripped their rifles and flicked the safeties. Joshua crossed the clearing. Lucas and Ann tagged closely.

From ground level, Joshua could not see the lake, but above the trees he could see the wall that he knew was adjacent to the lake. He entered the woods and at the fork took the trail on the right this time, heading toward that wall.

A herd of scarab beetles with luminescent racing stripes scattered from the path. Stickers blocked, waving like octopus tentacles. Joshua thrashed with his rifle barrel. The stickers fought back. He slashed with his knife. Hissing, the stickers parted, revealing the lakeside clearing. Bounding with half-gee leaps, Joshua reached the dry lake's shore.

Pack by pack, Lucas tossed a pile of explosive charges onto the corroded bottom. Then he backed from the shoreline and crouched. Joshua and Ann got behind him.

The lake bed boomed and a pillar of orange dust billowed roofward. Joshua ran to the edge. The cloud cleared, revealing ... a shallow crater.

"It hardly made a dent!" Ann cried.

"Joshua, that was it," Lucas said. "I have one charge left."

"Maybe," Joshua thought aloud, "the charge will have more effect if we cover it with rocks and--"

"One charge won't punch through two meters of steel!"

"Joshua," Ann said.

The tall grass by the woods was shivering. Out marched a carpet of leaves, marigold-epaulettes dancing and banner-sticks waving. Chanted squeals echoed against the module wall. From Joshua's right to his left, the rats advanced in a semicircle that constricted around the humans standing at the centerpoint of its radius.

Joshua raised his rifle, took aim, and fired. A rat leaped into the air and flopped. The humans spread rifle fire in a trisected pattern. Stampeding over the bloodied corpses of their stricken comrades, the rats retreated to the tall grass. But the grass continued to shiver.

"They're not going away," Joshua said.

"I told you, they're territorial!" Ann said.

"I think they've got us surrounded," Lucas said.

Suddenly the grass stilled. Then Joshua heard a loud squeal, followed by simultaneous clicks from everywhere in the grass before them.

Black rain-in-reverse erupted from the grass.

The dark speckles arched skyward and careened toward the humans. Joshua shielded with the carrybag and cringed. A hail of pebbles rapped against his helmet and arms and stung the ground.

"Catapults!" Lucas cried. " How can they have catapults?" In a fleeting instant, Joshua pictured miniature medieval-style catapults mounted on tiny wheeled carts with windlasses no larger than sewing-machine spools, ropes as thin as thread. Rationality told him the

"ratapults" could be no more than flexible sticks gouged into the ground and bent under the weight of a gangpile of rats. But all he saw, in a one-eighty panorama with his back to the lake bed and module wall, was furiously agitating tall grass.

He heard a rat shriek. The grass clicked. Another storm of projectiles streaked toward the humans. Rocks and beetles and clumps of muck pelted their suits. Under cover of catapult fire, the rats charged. The humans retreated into the lake bed.

They crowded side-to-side, scanning the lake's perimeter, which was then above eye level, and they waited for the rats to rush the edge. Conducting a mental inventory of their remaining ammo, Joshua wished he could trade his rifle for a chain saw.

"More clever than intelligent!" Lucas mumbled. "So they can't compose a symphony at us!" Abruptly, a riot of squeals came from above.

Joshua heard whinnying, then hoofbeats. A rat carcass tumbled onto the lake bed, flinging droplets of blood from its wounds. The humans climbed to the shoreline.

The unicorn galloped across the clearing, stamping the tall grass, dipping its head and swinging its horn like a metronome set to allegro. Skewered rats flew outward in waves as the rest scrambled. In seconds, the rats vanished. Their squeals faded into the woods. The unicorn made prancing circles and snorted. Joshua and Ann helped Lucas onto the grass.

Ann ran to Constance. "You saved us, sweetie! You're wonderful, you are!" Its neck enveloped in Ann's embrace, the creature grunted and bobbed its head, seemingly in agreement, giving Joshua the impression that modesty was a quality yet to be engineered into the Plantagenet Line. But there was no question, he admitted as he surveyed the piles of impaled and blood-soaked carcasses littering the field, that the battle had been well-fought.

Lucas peeled a wrapper and held out a bar. "Babe, you deserve a hundred more for that!" While the unicorn nibbled, Joshua gently brushed his fingertips against its hide. It was trembling, and beneath the hairs he traced tiny scars.

"She's fought quite a few battles," he said.

"We can't leave her here," Ann said.

"I know."

Joshua gazed at the shallow crater in the lakebed. Lucas and Ann turned their attention from Constance and gave him what-do-we-do-now-captain looks.

"Well," he said. "We have to figure another way out."

"Will the reactor melt a hole in the shell?" Lucas asked. "We could jump through that."

"The heat and radiation would fry us before then. This whole asterie will be super-heated into vapor." Lucas scowled. "Didn't our client tell you this place was harmless?"

"Toothless. Lucas, you want to try hacking into the system and overriding the self-destruct?"

"Even if I had all my gear--well, I'll try."

They started toward the lab. Ann's hand suddenly clutched Joshua's arm. She pointed to the trees. The bare branches drooped with squirming rats.

The humans froze and watched.

"Can they unlatch our helmets?" Lucas asked.

Ann's reply was barely a whisper. "Wouldn't put it past them." Joshua heard a crack from the trees. Another crack, and dirt exploded by his boots. Something metallic and rodlike glinted in the branches. An end of the rod sparked, and something whizzed by his helmet--far faster than a catapulted pebble.

"Get down!" he shouted.

They dropped to the grass as gunfire erupted from several trees at once. Bullets whizzed overhead and ricocheted against the module wall. Hugging the ground, the humans crawled to the shoreline and rolled onto the lake bed, into concealment from the arboreal snipers.

Ann whistled. "C'mon, Constance!"

With a leaping glide, the unicorn landed onto the rusted bottom. A rain of pebbles clattered after. Red streaks on Constance's haunches revealed where the missiles had grazed. Ann stopped hyperventilating only after she assured herself there were no bullet wounds.

"They must have broken into the armory," Joshua said, catching his breath. "Now we know what caused the evacuation."

"How can they know how to shoot?" Lucas asked.

"They must have seen humans doing it," Ann said. "They're very imit--" Another volley of bullets ricocheted against the module wall. Joshua examined the wall, surveying its entire length. It was a sheer plane of metal.

"I don't see any exits," he said.

"The module walls have to be sealed for waterproofing," Ann said. "They're different from the cargo walls."

Lucas hefted his last charge. "You mean, they don't move around?" Lucas climbed to the wall with a haste that belied his body-to-fat ratio. He set the charge, retreated to the basin, blasted a hole. It remained unplugged. Through the jagged gap, they slipped out of the ecosystem module, into a cargo compartment. With some coaxing, Ann got the unicorn to follow. Joshua looked back. The clearing showed a carpet of leaves rolling toward the hole, guns and rifles riding atop the swellings.

He checked his gyro compass and pointed right. "The hangar's this way." Ann petted and prodded the unicorn after them into the next room. Lucas ran to the next portal and yanked the handle. It refused to budge. He bored the lock mechanism with a number-three bit. He flung back the door and motioned.

Joshua looked at his suit clock. They had nearly an hour left, but what of it? They would be chased by rats through the maze, never coming even close to the exit, even if the keeper were to leave all the portals unlocked. For it would rearrange the walls, and escape would always be impossible. If only, Joshua thought, he could make the keeper realize their lives were in imminent danger from-Joshua halted. Another idea had come. He didn't think it was a good idea. The risk, for one thing, was far worse than blasting through the lake bed. If he was wrong, the rats would not forgive....

"Joshua--let's move!" Lucas shouted, waving toward the next portal. "Come on!"

"No," Joshua said. "Not that way." He referenced the compass arrow and nodded toward the hangar.

"This way."

"We can't go that way!" Lucas shouted. "There's no portal! Now come on--they're right behind us!"

"Exactly," Joshua said. He drew himself up. "And we need to get them around us, also." Lucas's mouth went slack. "Are you crazy?"

I wonder too, Joshua thought. "Lucas, we have to force the keeper to choose!" Pouring through the hole blasted from the module, the rats overflowed the previous room, abandoning their leaves as the camouflage was no longer of use. The humans took cover behind palleted cargo. The unicorn trembled and bucked, making threatening circles with her horn tip. Ann took a syringe from her med pack and jabbed the creature's flank. Constance calmed.

The rats charged. Joshua squeezed his trigger. They returned fire.

From overhead came skittering noises. A ceiling grid popped open, a rat head poked out. Joshua blasted it off its shoulders.

"The ventilator shafts!" Lucas cried. "They can go anywhere in the maze!"

"That's good," Joshua said. But he had his doubts. If the keeper didn't split the fine hairs of philosophical reasoning the same way that he did-" Joshua," the keeper's voice boomed from the ceiling grid. "You are being surrounded by creatures which I have determined are hostile to human life. You must move away. Please go through the portal on your right."

"No, Keeper," Joshua said.

"Joshua, this is a matter of your personal safety. Please go through the portal on your right." Lucas stepped toward the portal. Joshua grabbed him.

"No. Wait!"

Through the portal on his right, he watched the floor vanish beneath the mass of rats dropping from the ventilator shaft. Ann raised her rifle barrel. Joshua pulled it down.

"Let them come," he said. "Please trust me on this!" Anxiety kept him from articulating, but in his mind, he visualized the situation. He thought of the hangar as being at the asterie's North Pole. To reach the hangar and safety, they needed to go north. Rats were coming from the portal in the south. Through ventilator shafts, the rats had filled the rooms above and west. East was the module. Below was two meters of steel.

That left the humans only one way of escape from the rats. To the north--to the hangar.

"Keeper," Joshua said. "We're surrounded now, except for one room. You must open the wall to that room, or we will die. And you are responsible."

"No, Joshua. You are responsible for placing yourself in jeopardy."

"That was true, Keeper. However, now the situation is out of my control. Now you are responsible for whether we live or die."

The keeper was silent. The machine that could perform complex arithmetic calculations in picoseconds took humanly measurable time to contemplate ethical equations.

"Keeper," Joshua said, above the rising clamor of the rats. "This has nothing to do with your self-destruct sequence. You cannot claim an exception to your ethical programming. Open the wall, or the rats will kill us--and you are responsible!"

The keeper's programming instructed it to insert emotional intensity into its voice: " You must move, Joshua! You must move to another room!"

The rooms on the other sides of the portals seethed shin-deep in rats. Surely the keeper saw! Joshua feared: could a machine experience denial?

"It's too late for us to move anywhere without your help," Joshua said. Then, for the sake of his listeners--including himself--he forced his voice calm: "You must help us, Keeper ... or cause us to die by your inaction."

They waited. The rats howled. The room shook with the thrashing of the horde. Joshua heard a hum behind his back.

The wall to asterie-north rose into the ceiling, revealing the one still-ratless adjoining room.

"Joshua," the keeper said. "Move into the room I have opened--now!" The humans backstepped northward. The rats surged after. Lucas raced for the next portal. But it faced westward and he caught himself and nodded at Joshua. They waited for the rats to catch up.

"We have to do this one room at a time?" Ann asked. "All the way out?" The next northward wall opened. The humans stepped through.

The rats quickened the pace, emboldened by each retreat and enraged by each wall-raising escape. The keeper waited too long, sometimes. Joshua poured his bullet clip into the horde, attempting to keep the fangs beyond glove-nipping distance.

With somersaults and hops, the rats proved as adept as cinematic ninjas at evading Joshua's aim. They dodged the rifle snout and leaped onto his body. Their paws sought his external suit controls. They shut down his airflow fans. They ran his heater coils at full blast. They popped his ears with pressure charges. Worst of all, they scratched at the helmet locks.

His ammunition clip emptied. Lucas's gun clicked. Then Ann's. Then the humans used their firearms as clubs.

The keeper, finally recognizing their predicament, opened the remaining walls.

* * * *

With half an hour remaining until the point nine nine interval, they reached the end of the cargo spaces and entered the permanent decks of personnel quarters, and in the straight passages they shook the rats off their suits and outran the tiny legs of their pursuers. At last they reached the hangar. Joshua and Lucas cycled through the personnel airlock, unrolled and inflated the skiff's transport bubble. They pressed the seal against the transport docking mechanism. Ann swathed the horn tip inside bandages. With urging and shoving, a double-dosed Constance bemusedly trotted into the bubble. Then Ann stared toward the mouth of the hanger.

"Joshua, why are there two skiffs?"

When Joshua turned, there were not only two skiffs, but five men emerging from behind a fuel tank. One of the space suits was jet black with gold trim. Smiling through the face plate was the Lord of Scarborough.

"Greetings, Captain Wang," Emil Hamilton said. "All of you, drop your weapons. Bags too, please. Or would you rather we blow off your legs?"

Under the aim of five automatic rifles, Joshua, Lucas, and Ann released their bags and empty weapons.

"Prior to engaging your services," Hamilton said, "I contracted a team of Nemesis Commando Robots. Top-of-the-line strategic-reasoning AIs--augmented with state-of-the-art armor and weaponry. They entered that airlock behind you weeks ago, and have failed to return or signal. Their loss cost me far more than thirty thousand credits. So, Captain, I'm interested in learning how you solved the keeper's maze."

Joshua kept his eyes still, but took in the situation. In front of him, armed men blocked escape to Raven's skiff. Behind him, on the other side of the airlock ... yes. But he had to play for time ... to let one threat catch up to another.

"Before I tell you anything," Joshua said, "I'd like to know about your plans." Hamilton laughed. "I suppose I won't mind boasting."

"The unicorn was just a cover to do business with Daedalus Genetics, right? You really wanted intellirats."

"Very good."

"But what do you want intellirats for?"

"Surely that's obvious. I want them for what everyone else wants them for. As a weapon, to infest other people's asteries."

"But why would an asterie developer want to damage asteries?"

"Let me explain the process. It all has to do with Scarborough. Scarborough is a tourist attraction. When the tourists go home, they take the rats with them aboard their return shuttles. Unknowingly, of course. Then the rats infest the tourists' home asteries. My consortium buys the infested asteries at depressed prices. Then we exterminate the rats, and sell the rat-free asteries at market prices. We make a considerable profit, and will be regarded as saviors of otherwise uninhabitable asteries."

"So long as no one tells the secret."

Hamilton smiled thinly.

Joshua glanced at his crew. Their eyes were wide, fixated on the gun barrels aimed at their chests. Joshua continued: "I don't see how you expect to get rid of the intellirats, when even Daedalus Genetics couldn't."

"This asterie was overrun by an earlier, less controllable version of intellirats," Hamilton replied. He gestured toward their carrybags. "Those particular embryos have been engineered to grow an organic antenna inside the skulls. The proper coded radio signal, at the correct frequency, and the rats die instantly, en masse."

"But isn't there a problem getting them into other people's asteries in the first place? All the inspections, the detectors, the scanners--"

"The rats are designed to survive briefly in vacuum--expanded lung capacity, pressure-barrier skin layers, even hibernation ability. Thus, they can ride on the outside of shuttles, and hop into asterie hangars after docking. And they can operate airlocks."

"I'm sure. But then--"

"Excuse me, Captain. You're not thinking of prolonging this until the reactor melts, are you?" A smirk blossomed on Hamilton's face. "And yes, the keeper was thoughtful enough to warn us about that." Joshua said nothing. Lucas growled at the ceiling camera: "Traitor!" Hamilton checked his watch. "We'll need to leave soon. So are you going to explain how you escaped the maze?"

"Certainly," Joshua said. "It was very simple. The crew helped us." Hamilton's smirk faded.

"The--personnel? They've evacuated!"

"Not all." Joshua tilted his head toward the hangar ceiling camera, as if acknowledging an audience. As his men shifted footings, Hamilton glared at Joshua. "You're lying."

"Look at the three of us. Not exactly paramilitary material, wouldn't you say? But your commando robots never came out, and we did. It's because we had help."

Hamilton shouted at the camera: "My yacht has missiles! I'm warning you!"

"You're not really sure this place is toothless, are you?" Joshua asked. "And your relationship with Daedalus Genetics hasn't been friendly, either. Not lately. Not since you've been boarding without permission."

Hamilton locked his eyes on Joshua. "You're lying! There's no one here!"

"See for yourself."

"You!" Hamilton pointed to one of his men, then at the airlock. "Go inside, check! No more than one minute, then come out!"

With a nervous glance at his companions, the man approached the airlock. He pressed the button. The door slid open. He stepped inside. The door slid closed. Hustling Joshua and Lucas to one side, Hamilton motioned his other men into firing positions directly in front of the airlock.

Joshua waited, tensing his muscles. Lucas studied the bare deck. Ann gazed blankly and stroked Constance's mane. The airlock door slid open.

Out lunged a screaming man--and a thousand angry rats.

Whirling and staggering, Hamilton and his henchmen frantically grabbed and flung furry bodies from their space suit controls. During the wild dance, one man's rifle fell to the deck. Mindful of the clinging vermin, Joshua slowly edged toward the abandoned weapon.

* * * *

Approximately half an hour later, having doffed his space suit, Joshua sat in the control room of Raven and watched the pilot's main screen as the skiff bearing Hamilton's henchmen returned to its yacht. Then Daedalus spewed incandescent and radioactive vapor into surrounding space. The gasses first emanated from the hangar, then from the vents, and then from holes melted along the rim as chunks of the reactor fell through. Finally, the microworld vanished within clouds of superheated mist.

"All the stuff we could have salvaged," Lucas said. "It's not doing anyone any good now."

"Be thankful we got out alive," Ann said.

"Maybe we can get a reward, too," Joshua said. "It depends whether our guest has a price on his head." He turned to their prisoner. Hamilton struggled with his bonds, but Ann had secured the knots. While continuing to watch the screen, Lucas casually kept a pistol aimed at the small of Hamilton's back. Hamilton formed his face into a snarl. "Wang, listen! My ship has you outgunned. They're under orders not to accept hostage threats. You may as well surrender right now, because you're not going anywhere!"

"Let me show you why we are," Joshua said.

Joshua clicked screen icons, opening an application window that displayed a graphic of the ships and asterie. Daedalus was interposed between the salvage ship and the space yacht. From the holes in its equator, the spinning worldlet gushed expanding spirals of vapor.

"See this disk-shaped cloud?" Joshua asked. "It's what remains of the interior of Daedalus. Hundreds of thousands of tons of material, converted to plasma-hot gasses. And I've maneuvered so that the disk serves as an impenetrable barrier between our ships. By the time it disperses, we'll be long gone." Hamilton glared at the screen, then at Joshua. "You won't get far! My ship is faster than yours!"

"You've never navigated through the Asteroid Belt, have you?"

"What's that supposed to mean?"

"Speed isn't everything. Besides, Raven is faster than you think." Joshua smiled at Ann. "You have a place to put him?"

"In the main hold with Constance," Ann replied. "If she can take the smell." Lucas helped Ann escort Hamilton away. Joshua returned his eyes to his console and tapped keys. The screen displayed a real-time map of the Asteroid Belt, with their current position superimposed upon a shifting field of asteroids, asteries, and spaceships. Sipping his espresso, Joshua touched the stylus to the screen--marking possible courses, identifying potential intercepts. He was still working when Lucas returned.

"So who gets him?" Lucas asked.

Joshua sighed, resting a hand on the screen. "I'm still analyzing and tagging the scanner contacts--friends, foes, neutrals, pirates, and sovereignties that might take him. Then I have to figure how to weave around intercept ranges and spheres of influence."

Lucas twitched a smile. "Looks like a dynamic maze."

"It's a mess. Everything in different orbits, changing vectors on whim. Long-range transits in the Belt are always miserable for navigators, thanks to the political chaos."

"You'd like the Belt united under one government."

Joshua shook his head.

"That would be like having a keeper run everything. And there'd be no escape." He set a course. The ship got under way, and they entered the maze.

Copyright 2006 Joe Schembrie

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"The greatest dangers to liberty lurk in insidious encroachment by men of zeal, well-meaning but without understanding."

--Louis D. Brandeis