Caliban's War

by James S. A. Corey

  Prax had watched it too, as had everyone on his team. For him, it had been a puzzle. The drive to apply the logic of conventional biology to the effects of the protomolecule had been overwhelming and, for the most part, fruitless. Individual pieces were tantalizing—the spiral curves so similar to nautilus shell, the heat signature of the infected bodies shifting in patterns that almost matched certain hemorrhagic fevers. But nothing had come together.

  Certainly someone, somewhere, was getting the grant money to study what had happened, but Prax’s work wouldn’t wait for him. He’d turned back to his soybeans. Life had gone on. It hadn’t been an obsession, just a well-known conundrum that someone else was going to have to solve.

  Prax hung weightless at an unused station in ops and watched the security camera feed. The creature reached out for Captain Holden, and Holden shot it and shot it and shot it. Prax watched the filamentous discharge from the creature’s back. That was familiar, certainly. It had been one of the hallmarks of the Eros footage.

  The monster began to tumble. Morphologically, it wasn’t very far off from human. One head, two arms, two legs. No autonomous structures, no hands or rib cages repurposed to some other function.

  Naomi, at the controls, gasped. It was odd, hearing it only through the actual air they shared and not through the comm channel. It seemed intimate in a way that left him a little uncomfortable, but there was something more important. His mind had a fuzzy feeling, like his head was full of cotton ticking. He recognized the sensation. He was thinking something that he wasn’t yet aware of.

  “I’m pinned,” Holden said. “I need you to cut the mags on this crate.”

  The creature was at the far end of the cargo bay. As Amos went in, it braced itself with one hand, throwing a large crate with the other. Even in the poor-quality feed, Prax could see its massive trapezius and deltoids, the muscles enlarged to a freakish degree. And yet not particularly relocated. So the protomolecule was working under constraints. Whatever the creature was, it wasn’t doing what the Eros samples had done. The thing in the cargo bay was unquestionably the same technology, but harnessed for some different application. The cotton ticking shifted.

  “No! Stop opening the damn door. I’m trapped behind two goddamn crates now.”

  The creature moved back to the bulkhead, near where it had first been at rest. It huddled there, the wounds in its body pulsing visibly. But it hadn’t settled there. With the engines off-line, there wasn’t even a trace of gravity to pull it back in place. If it was comfortable there, there had to be a reason.

  “No!” Naomi said. Her hands were on the support rings by the controls. Her face had an ashy color. “No. Look where Holden is under those crates. If we go high g, it’ll break every bone in his body, even if he somehow isn’t thrown out the door too.”

  “Yeah, she’s right,” Amos said. He sounded tired. Maybe that was how he expressed sorrow. “That plan’ll kill the captain. It’s off the table.”

  “Well. A high-g burn would almost certainly break me into tiny pieces right now. But that doesn’t necessarily take it off the table.”

  On the bulkhead, the creature moved. It wasn’t much, but it was there. Prax zoomed in on it as best he could. One massive clawed hand—clawed but still with four fingers and a thumb—braced it, and the other tore at the bulkhead. The first layer was fabric and insulation and it came off in rubbery strips. Once it was gone, the creature attacked the armored steel underneath. Tiny curls of metal floated in the vacuum beside it, catching the light like little stars. Now why was it doing that? If it was trying to do structural damage, there was any number of better ways. Or maybe it was trying to tunnel through the bulkhead, trying to reach something, following some signal …

  The cotton ticking disappeared, resolving into the image of a pale, new root springing from a seed. He felt himself smile. Well, that’s interesting.

  “What is, Doc?” Amos asked. Prax realized he must have spoken aloud.

  “Um,” Prax said, trying to gather the words that would explain what he’d seen. “It’s trying to move up a radiation gradient. I mean … the version of the protomolecule that was loose on Eros fed off radiation energy, and so I guess it makes sense that this one would too—”

  “This one?” Alex asked. “What one?”

  “This version. I mean, this one’s obviously been engineered to repress most of the changes. It’s hardly changed the host body at all. There have to be novel constraints on it, but it still seems to need a source of radiation.”

  “Why, Doc?” Amos asked. He was trying to be patient. “Why do we think it needs radiation?”

  “Oh,” Prax said. “Because we shut down the drive, and so the reactor is running at maintenance level, and now it’s trying to dig through to the core.”

  There was a pause, and then Alex said something obscene.

  “Okay,” Holden said. “There’s no choice. Alex, you need to get that thing out of here before it gets through the bulkhead. We don’t have time to build a new plan.”

  “Captain,” Alex said. “Jim—”

  “I’ll be in one second after it’s gone,” Amos said. “If you aren’t there, it’s been an honor serving with you, Cap.”

  Prax waved his hands, as if the gesture could get their attention. The movement sent him looping slowly through the operations deck.

  “Wait. No. That is the new plan,” he said. “It’s moving up a radiation gradient. It’s like a root heading toward water.”

  Naomi had turned to look at him as he spun. She seemed to spin, and Prax’s brain reset to feeling that she was below him, spiraling away. He closed his eyes.

  “You’re going to have to walk us through this,” Holden said. “Quickly. How can we control it?”

  “Change the gradient,” Prax said. “How long would it take to put together a container with some unshielded radioisotopes?”

  “Depends, Doc,” Amos said. “How much do we need?”

  “Just more than is leaking through from the reactor right now,” Prax said.

  “Bait,” Naomi said, catching hold of him and pulling him to a handhold. “You want to make something that looks like better food and lure that thing out the door with it.”

  “I just said that. Didn’t I just say that?” Prax asked.

  “Not exactly, no,” Naomi said.

  On the screen, the creature was slowly building a cloud of metal shavings. Prax wasn’t sure, because the resolution of the image wasn’t actually all that good, but it seemed like its hand might be changing shape as it dug. He wondered how much the constraints placed on the protomolecule’s expression took damage and healing into account. Regenerative processes were a great opportunity for constraining systems to fail. Cancer was just cell replication gone mad. If it was starting to change, it might not stop.

  “Regardless,” Prax said, “I think we should probably hurry.”

  The plan was simple enough. Amos would reenter the cargo bay and free the captain as soon as the bay doors had shut behind the intruder. Naomi, in ops, would trigger the doors to close the moment the creature had gone after the radioactive bait. Alex would fire the engines as soon as doing so wouldn’t kill the captain. And the bait—a half-kilo cylinder with a thin case of lead foil to keep it from attracting the beast too early—would be walked out through the main airlock and tossed into the vacuum by the only remaining crewman.

  Prax floated in the airlock, bait trap in the thick glove of the environment suit. Regrets and uncertainty flooded through his mind.

  “Maybe it would be better if Amos did this part,” Prax said. “I’ve never actually done any extravehicular anything before.”

  “Sorry, Doc. I’ve got a ninety-kilo captain to haul,” Amos said.

  “Couldn’t we automate this? A lab waldo could—”

  “Prax,” Naomi said, and the gentleness of the syllable carried the weight of a thousand get-your-ass-out-theres. Prax checked the seals on his suit one more time. Everything reported good.
The suit was much better than the one he’d worn leaving Ganymede. It was twenty-five meters from the personnel airlock near the front of the ship to the cargo bay doors at the extreme aft. He wouldn’t even have to go all the way there. He tested the radio tether to make sure it was clipped tightly into the airlock’s plug.

  That was another interesting question. Was the radio-jamming effect a natural output of the monster? Prax tried to imagine how such a thing could be generated biologically. Would the effect end when the monster left the ship? When it was burned up by the exhaust?

  “Prax,” Naomi said. “Now is good.”

  “All right,” he said. “I’m going out.”

  The outer airlock door cycled open. His first impulse was to push out into the darkness the way he would into a large room. His second was to crawl on his hands and knees, keeping as much of his body against the skin of the ship as humanly possible. Prax took the bait in one hand and used the toe rings to lift himself up and out.

  The darkness around him was overwhelming. The Rocinante was a raft of metal and paint on an ocean. More than an ocean. The stars wrapped around him in all directions, the nearest ones hundreds of lifetimes away, and then more past those and more past those. The sense of being on a tiny little asteroid or moon looking up at a too-wide sky flipped and he was at the top of the universe, looking down into an abyss without end. It was like a visual illusion flipping between a vase and then two faces, then back again at the speed of perception. Prax grinned up, spreading his arms into the nothingness even as the first taste of nausea crawled up the back of his tongue. He’d read accounts of extravehicular euphoria, but the experience was unlike anything he’d imagined. He was the eye of God, drinking in the light of infinite stars, and he was a speck of dust on a speck of dust, clipped by his mag boots to the body of a ship unthinkably more powerful than himself, and unimportant before the face of the abyss. His suit’s speakers crackled with background radiation from the birth of the universe, and eerie voices whispered in the static.

  “Uh, Doc?” Amos said. “There a problem out there?”

  Prax looked around, expecting to see the mechanic beside him. The milk-white universe of stars was all that met him. With so many, it seemed like they should sum to brightness. Instead, the Rocinante was dark except for the EVA lights and, toward the rear of the ship, a barely visible white nebula where atmosphere had blown out from the cargo bay.

  “No,” Prax said. “No problems.”

  He tried to take a step forward, but his suit didn’t budge. He pulled, straining to lift his foot from the plating. His toe moved forward a centimeter and stopped. Panic flared in his chest. Something was wrong with the mag boots. At this rate, he’d never make it to the cargo bay door before the creature dug through and into engineering and the reactor itself.

  “Um. I have a problem,” he said. “I can’t move my feet.”

  “What are the slide controls set to?” Naomi asked.

  “Oh, right,” Prax said, moving the boot settings down to match his strength. “I’m fine. Never mind.”

  He’d never actually walked with mag boots before, and it was a strange sensation. For most of the stride, his leg felt free and almost uncontrolled, and then, as he brought his foot toward the hull, there would be a moment, a critical point, when the force took hold and slammed him to the metal. He made his way floating and being snatched down, step by step. He couldn’t see the cargo bay doors, but he knew where they were. From his position looking aft, they were to the left of the drive cone. But on the right side of the ship. No, starboard side. They call it starboard on ships.

  He knew that just past the dark metal lip that marked the edge of the ship, the creature was digging at the walls, clawing through the flesh of the ship toward its heart. If it figured out what was going on—if it had the cognitive capacity for even basic reasoning—it could come boiling up out of the bay at him. Vacuum didn’t kill it. Prax imagined himself trying to clomp away on his awkward magnetic boots while the creature cut him apart; then he took a long, shuddering breath and lifted the bait.

  “Okay,” he said. “I’m in position.”

  “No time like the present,” Holden said, his voice strained with pain but attempting to be light.

  “Right,” Prax said.

  He pressed the small timer, hunched close to the hull of the ship, and then, with every muscle in his body, uncurled and flung the little cylinder into nothing. It flew out, catching the light from the cargo bay interior and then vanishing. Prax had the nauseating certainty that he’d forgotten a step, and that the lead foil wouldn’t come off the way it was supposed to.

  “It’s moving,” Holden said. “It smelled it. It’s going out.”

  And there it was, long black fingers folding up from the ship, the dark body pulling itself up to the ship’s exterior like it had been born to the abyss. Its eyes glowed blue. Prax heard nothing but his own panicked breathing. Like an animal in the ancient grasslands of Earth, he had the primal urge to be still and silent, though through the vacuum, the creature wouldn’t have heard him if he’d shrieked.

  The creature shifted; the eerie eyes closed, opened again, closed; and then it leapt. The un-twinkling stars were eclipsed by its passage.

  “Clear,” Prax said, shocked by the firmness of his voice. “It’s clear of the ship. Close the cargo doors now.”

  “Check,” Naomi said. “Closing doors.”

  “I’m coming in, Cap’n,” Amos said.

  “I’m passing out, Amos,” Holden said, but there was enough laughter in the words that Prax was pretty sure he was joking.

  In the darkness, a star blinked out and then came back. Then another. Prax mentally traced the path. Another star eclipsed.

  “I’m heating her back up,” Alex said. “Let me know when you’re all secure, right?”

  Prax watched, waited. The star stayed solid. Shouldn’t it have gone dark like the others? Had he misjudged? Or was the creature looping around? If it could maneuver in raw vacuum, could it have noticed Alex bringing the reactor back online?

  Prax turned back toward the main airlock.

  The Rocinante had seemed like nothing—a toothpick floating on an ocean of stars. Now the distance back to the airlock was immense. Prax moved one foot, then the other, trying to run without ever having both feet off the deck. The mag boots wouldn’t let him release them both at the same time, the trailing foot trapped until the lead one signaled it was solid. His back itched, and he fought the urge to look behind. Nothing was there, and if something was, looking wouldn’t help. The cable of his radio link turned from a line into a loop that trailed behind him as he moved. He pulled on it to take up the slack.

  The tiny green-and-yellow glow of the open airlock called to him like something from a dream. He heard himself whimpering a little, but the sound was lost in a string of profanity from Holden.

  “What’s going on down there?” Naomi snapped.

  “Captain’s feeling a little under the weather,” Amos said. “Think he maybe wrenched something.”

  “My knee feels like someone gave birth in it,” Holden said. “I’ll be fine.”

  “Are we clear for burn?” Alex asked.

  “We are not,” Naomi said. “Cargo doors are as closed as they’re going to get until we hit the docks, but the forward airlock isn’t sealed.”

  “I’m almost in,” Prax said, thinking, Don’t leave me here. Don’t leave me in the pit with that thing.

  “Right, then,” Alex said. “Let me know when I can get us the hell out of here.”

  In the depth of the ship, Amos made a small sound. Prax reached the airlock, pulling himself in with a violence that made the joints of his suit creak. He yanked on his umbilical to pull it the rest of the way in after him. He flung himself against the far wall, slapping at the controls until the cycle started and the outer door slid closed. In the dim light of the airlock proper, Prax spun slowly on all three axes. The outer door remained closed. Nothing ripped it open;
no glowing blue eyes appeared to crawl in after him. He bumped gently against the wall as the distant sound of an air pump announced the presence of atmosphere.

  “I’m in,” he said. “I’m in the airlock.”

  “Is the captain stable?” Naomi asked.

  “Was he ever?” Amos replied.

  “I’m fine. My knee hurts. Get us out of here.”

  “Amos?” Naomi said. “I’m seeing you’re still in the cargo bay. Is there a problem?”

  “Might be,” Amos said. “Our guy left something behind.”

  “Don’t touch it!” Holden’s voice was harsh as a bark. “We’ll get a torch and burn it down to its component atoms.”

  “Don’t think that’d be a good idea,” Amos said. “I’ve seen these before, and they don’t take well to cutting torches.”

  Prax levered himself up to standing, adjusting the slides on his boots to keep him lightly attached to the airlock floor. The inner airlock door chimed that it was safe to remove his suit and reenter the ship. He ignored it and activated one of the wall panels. He switched to a view of the cargo bay. Holden was floating near the cargo airlock. Amos was hanging on to a wall-mounted ladder and examining something small and shiny stuck to the bulkhead.

  “What is it, Amos?” Naomi asked.

  “Well, I’d have to clean some of this yuck off it,” Amos said. “But it looks like a pretty standard incendiary charge. Not a big one, but enough to vaporize about two square meters.”

  There was a moment of silence. Prax released the seal on his helmet, lifted it off, and took a deep breath of the ship’s air. He switched to an outside camera. The monster was drifting behind the ship, suddenly visible again in the faint light coming out of the cargo bay, and slowly receding from view. It was wrapped around his radioactive bait.