The Killer Thing

by Kate Wilhelm

  He sat up, completely awake in an instant. The radiation detector! He adjusted the light and read the screen that showed a blip of light on the farthest concentric line, moving inward so slowly that it was painful to watch. Four miles, and coming his way.

  He checked the hatch and raised the seat-bed to operating position, and then there was nothing else to do except wait for it to get closer. It was still very dark outside. He had slept less than seven hours. How had it found him so quickly this time? Why hadn’t it gone out on the sands after him?

  It’s a logic machine, Trace. Whatever you can reason out, so can it. Don’t forget that, or you’re lost. Use your humanness on it, your instincts, your intuition, anything that isn’t a part of logical planning. You can’t beat it at its game.

  Yeah, Duncan, I tried that, twice now. The first time it didn’t see me take out over the desert, but this time it did. I was sure to let it see which way I was going. It didn’t follow me, Duncan.

  Logic machine, Trace. Simple logic machine.

  Trace shook his head impatiently, willing the whispering voice away. The blip was not coming straight at him; it was heading south. It was zigzagging, searching for him among the mammoth rock formations. He expelled a long sigh when the beeping voice of the detector abruptly stopped. It had passed out of range.

  It would be back, all he had gained was a matter of extra minutes. He touched his lips; they were cracked and sore, and for the first time he became aware of a curious distant ringing in his ears, and a burning in his eyes. He rummaged in the medical supplies and came up with anti-fever capsules. As his hand groped for the water bags, he rose up sharply. There were only two of them left, one partially emptied. He remembered the dream, swimming in cold, fresh water, and his gaze swung around to the seat-bed where he saw the bag, inert and empty. He cursed harshly, picked up the bag, and threw it against the wall of the dinghy. He had crushed one of the capsules, and he flung the granular medicine from him also, swallowing the other one dry. The screen continued blank, the system silent, and he made a scant breakfast on prepared emergency rations, squeeze tubes of concentrated foods that tasted pasty and disgusting. He paid little attention to which of them he grabbed from the dwindling stock. Food wouldn’t be a problem. It would be abundant long after he was dead from thirst.

  He refused the thought. Death came in space, in battle, with a tearing pain that killed before the brain received the pain signal. Or it came when a faulty pressure suit exploded, or when a ship’s pile flared without warning. Death had many approaches, but it would not catch him alone on a planet where no other man walked.

  His audio system picked up the first sigh of the wind, a long soft rustle of noise that was like a silken cloth stirring. Dawn. In forty minutes he would have to move whether or not the killer robot again entered the circle of his screen. His jaw was tight. Where could he go this time? He had run out of mountains to hide in, and behind him the ground was crisscrossed with “hot” rocks that would throw his radiation detection system way the hell out. He had led the thing six hundred miles, and, as obedient as a dog, it had followed every step of the trail, never slowing down or faltering or making a mistake. He gnawed on a knuckle and stared at his screen, the wind noises now steady in his ears, and he visualised the backbone of the mountain range with its jutting rocks and pocked ground. Six hundred miles long, and he could move only one hundred miles more before the fuel was gone, before he would be using the fuel he needed to return to his orbiting ship. He had to wait six days before he returned to his ship. The killer robot might kill him on the ground, but the lack of reserve oxygen would kill him in space. If only he had been able to hide…

  Or, he thought, he could make the whole jump, back to the other end, back to the beginning, and he could look for the robot’s dinghy. It had fuel in it. In time, even though it was hidden by the shield of invisibility, he would find it. If he had to drag his detector over every square inch of the ground, he would find it. And if he didn’t… The wind screamed, increasing in intensity as the sun rose higher over the horizon, heating the chilled night air, sucking it high into the frigid upper atmosphere. Trace clamped his hands over his ears so he could think without the maniacal voice shrilling at him. If he didn’t find the robot’s dinghy, and if the relief ship didn’t orbit before the robot caught up with him, it would get away.

  It would return to its own damaged dinghy, make the repairs needed, and leave this hellish desert. In space it would take the Fleet ship that Trace had left, and repair that. Where would it go next? Trace thought of his ship, his first ship, in the hands of the metal killer, and he felt hatred pour through him, drenching his skin with sweat, knotting his stomach. Even if he continued the hop and run flight it would be only two days before he would have used the precious supply of available fuel, and then he would have to leave the planet and sit in the orbiting ship, waiting for it to appear and take him there in space. It would take him with ease, the crippled ship would offer no resistance. It wouldn’t matter to it if the ship got “hot” or had no pressure, or no oxygen. It would be able to fix it enough to escape, and then, lost again in deep space, it would have all the time in the galaxy to repair the ship properly.

  “I have to keep it on the ground. I have to keep it away from its lifeboat, and away from mine. I can boobytrap mine, and the other one, if I find it. Not good enough. It will attack and kill the relief crew. They won’t be expecting it. The end will be the same…”

  The radiation beep startled him so that he jerked. It was advancing again, three miles away. It was time to go.

  “Okay, we shoot the works. I’m going to find it, you hear me? And I’m going to fix it so that it won’t fly. Then I’m going to take your fuel and the oxygen tanks and leave you here! You can tramp up and down this piece of hell for eternity! You can have this stinking planet! Your own kingdom. You can be god of everything on it! Do you hear me?”

  Trace heard his own shriek over that of the wind, and he closed his eyes hard for a moment. He turned on the engines and eased the dinghy out from under the sheltering ledge, and immediately the wind smashed into it, making it shudder. He clamped his mouth and fought the wind, getting the small lifeboat airborne, heading back. The wind buffeted him, sending his instrument needles skittering again and again, and after twenty minutes of the struggle, he knew he had to land or be torn to pieces by one of the tornadoes. His ground distance indicator said he had gone nine hundred and twenty miles. He knew there could be no second-guessing now. There no longer was enough fuel in his little craft to return to the ship.

  The robot would waste some time searching for him. It couldn’t know about the very human ability to gamble on a long shot; this was not a decision built on the firm ground of pure logic. Even allowing it one whole day for the vain search, Trace had only six days before he could expect it to show again on his screen. Six days in which to find the invisible dinghy, get its fuel, sabotage it, and leave the planet.

  Six

  Manoeuvring in the high wind among the sand-sculpted mountains was impossible; the air was black with sand and the tornado funnels whirled and flung rocks from pebble size to massive boulders. Trace chose a high, broad-based, up thrusting shaft of granite and came to a stop. His back muscles ached, as did his arms. His eyes were burning as if the sand had blasted them too. He let his head drop to his arms and sat unmoving several minutes, hearing only the howling wind punctuated with explosive blasts of rocks hitting rocks.

  How did the robot avoid the flying debris? Trace tried to visualise it being struck again and again, and still managing to stay upright and advancing. Had it learned to dodge them, to stay behind boulders when the winds rose?

  It’s smart, Duncan, real smart. It can learn from experience. It has to be that it is continually learning. The rocks would cripple it otherwise.

  Logic predicts the future on the basis of the past.

  Yeah, but, listen, Dunc. It isn’t just using what it had been programmed to know. Don’t you
see that? It is learning new things. And no one is here to programme them in. It’s doing it alone.

  Trace lifted his head and stared at the controls. Wearily he pushed himself from the seat and made his way to the rear of the boat where the supplies were. The fever was returning, and with it, the queer lightheadedness that meant danger. What if he became delirious here? He held the capsules and wondered if he had taken one or two of them earlier. He couldn’t remember. He swallowed two of them this time, washing them down with a mouthful of water. Very carefully he returned the water bag and locked the unit; he put the key in the medical supply section. The wind was growing noisier minute by minute; it would reach its peak momentarily, and then start to lessen. He had to know where he was going and take off as soon as the wind died.

  It would be pleasant to rest. Rest and get over the fever, regain his strength… A chill shook him and, frightened, he pulled out the map he had made of the planet. He had to go on. If he stayed where he was and died, the robot would find him in two days, be back at its own dinghy in another three.

  He had said it so casually ― if he died there. He tasted the words, repeated them aloud. Not in space then? Not to be flung from a ship to drift endlessly through black space? Nor yet to be buried on one of the worlds where the fleet had landed and conquered? He laughed and the sound of his voice startled him. The wind had died down completely.

  He stood up and gazed out of the port. How long had he been sitting there? It seemed less than minutes, but had been almost two hours. The chill returned, this time not on his skin, but deeper. He went back to the controls, and took off heading south, keeping to the edge of the mountain’s backbone, not flying out over the desert this time. The robot wouldn’t go out there anyway. The manoeuvre simply wasted time and fuel. His mind seemed very clear then; the capsules had fought the fever down again. He would find a good place to dig in, and then he would eat and rest through the hot part of the day. In the evening he would start his search for the hidden dinghy. It seemed so simple now. He remembered his thoughts of dying and he smiled grimly. Not yet. Not here. For three months the man and the machine had been tied together; not for nothing, he told himself fiercely. Not for nothing!

  He had been with Lar when Duncan found him. And he had left Lar in order to chase the metal monster. He refused to think of her. Later, when he had time to recall the nuances of her voice, the shades of meaning behind each motion she made, the way the shifting light caught the sparkle of her eyes, and then hid it… Grimly he stared at the finder scope, the crosshairs approaching his approximate destination. He had returned to the southern edge of the mountain range. He slowed and gained altitude, searching the ground below for the right place, for the spot where he had landed the dinghy for the first time.

  From up there he could see the shadows too well. Deep, black, long, still, distorted monoliths, towers, and peaks. The shadows changed the land, making it look new to his eyes, unfamiliar. He climbed higher and slowed still more. None of it looked like the spot he remembered. It was the same as all the rest, and yet different. Three miles south the mountains ended, with a streamer of disconnected rocks and boulders showing through the sand, and then the start of the endless ripples of low hills. The mountain was only fourteen miles wide at this point.

  It was there, somewhere beneath him that he had brought the boat down in the first place, with Duncan dying at his side.

  We’ll find a better place later, Duncan. Now all I want is to land and get you fixed up. Duncan? You awake?

  Sure, Trace.

  What happened to Duncan’s voice? It was as if he was speaking through a foot of gauze. Trace headed straight down, braking sharply, to land at the foot of a black cliff that rose over two hundred feet above them. He turned to Duncan who was the colour of wet putty.

  Okay, boy. Now we see what we can do about…

  Don’t touch me, Trace. I’m broken inside…

  Blood on his lips, frothy, mixed with air… His lungs?

  I’ll rig up an oxygen tent, Dune. Breathe easier then until the ship gets here. Matter of only a few days. We’re in the shade, plenty of food, water. You’re going to be all right, Dune. Take it easy, okay?

  Forget it, Trace. Fix the boat… Make sure the thing died…

  I will, Duncan. Later, after I finish the tent.

  He used the plastic, fitting it tightly with a strap around Duncan’s waist, securing it under the foam seat, with the oxygen hose entering from underneath near Duncan’s shoulder. Duncan didn’t move; his eyes were bright with pain, the whispering voice thick, almost unrecognisable.

  The sun heated the rocks, and they radiated. The sand threw heat from itself. The interior of the dinghy became hotter, and the air conditioner failed to relieve it. Trace bathed Duncan in cool water, injected him with pain controllers. Duncan’s laboured breathing eased after the injection and his eyes stopped their restless roving. Trace left him and repaired the hole in the dinghy, six inches in diameter, with neat edges. He mended the hole with the sun on his back, and when he re-entered the dinghy his suit was drenched, as if he had been swimming. Duncan was hot and dry, and asleep. He bathed him again, leaning low to catch the whispered voice:

  Save it, Trace. You’ll need it. The oxygen too.

  Duncan hadn’t opened his eyes. His face was different.

  He appeared to be younger; lines were easing out of his face, the relaxing effects of the drug. He looked almost happy.

  Make sure it died, Trace. Please!

  Sure, Dunc, sure. Sleep now, pal.

  Outside again, Duncan asleep inside. The black cliff over his head, the sun low, making the shadows grow along the ground. He walked around the cliff and found that he could clamber up it to a ledge that would afford him a good view of the surrounding land. He had to stop to rest many times, and the shadows continued to grow, striping the land now. Black, white, black… On the ledge he rested once more, and then began studying the land, sorry that he hadn’t waited until the following day when there would be no shadows, knowing also that he wouldn’t have been able to climb the cliff under the hot sun. He stared until his eyes ached, and then he saw it.

  It was impossible that it could have survived the landing, but it was there. The boat was badly damaged. Trace was several miles away from the robot at work on the craft, but he could see dents and a long gash in the side of the lifeboat. He could see the tools in the robot’s waldoes.

  Had he signalled to it? He didn’t think so. But somehow it sensed his watching presence, from the three or four miles distance. It turned the dome of its head. The lowering sun reflected on the metal as it turned, flashed green from one of the slits. The robot and the man faced one another for several seconds, too far apart for either to hurt the other, and the robot flicked off. Then the dinghy vanished. Trace remained for another moment, too stunned to move, and he felt the icy touch of fear. He slipped, slid, and fell back down the cliff the way he had gone up it, and raced back to the dinghy.

  It’s there, Dunc! It knows we are here! It blinked out, Duncan! Just like that, it blinked out. The dinghy too. There, and then gone. It’s got something new, a shield to hide behind. We have to get out of here, Dunc, before it comes.

  He took off, straight up, and headed north, the start of his long flight. He flew less than a hundred miles, afraid for Duncan’s sake to continue longer. When he landed the wind was high, getting higher.

  It’s a hellhole, Duncan. Sand and heat and now wind storms. And the robot. We’ll have to keep out of its path, try to find a way to get close enough to it to finish it off. Damn, I wish we had some artillery…

  Duncan didn’t answer him, and he bathed the unconscious man again. This time Duncan didn’t rouse at the touch of the cool water. The wind increased and the air inside the craft chilled with the coming of night. Duncan didn’t stir.

  It’s a logic box, that’s all. A logic box. But we don’t know what’s been programmed into it. We’ll have to take it for granted that its first order
of business will be to kill us. It has strong self-preservation goals, and we are a threat to its being. So we’ll have to assume that we’ve become the hunted now. How about that, Duncan? After hunting it for three months, now we’ve found it, and it’s the hunter. Duncan?

  Only the wind answered him. The wind died and the night was eerily quiet, then the wind was born again, and with its next interlude of quiet the sun was there. Trace continued to talk to Duncan throughout the night. Several times, when the fever rose, he bathed him. Duncan died when the sun was directly overhead and there were no shadows on the ground.

  Numbly Trace carried him from the ship to the edge of the desert, half a mile away, and there he scooped out a shallow grave and placed Duncan in it. He covered him with sand and built a cairn of rocks over the grave, and as he made his way back to the dinghy, a laser touched the grave, melted the rocks, glazed the sand around the rocks, found Duncan and played over his body until it no longer existed. Trace was turning for a last look before stepping around a granite slab, when he saw the rising puff of steam and smoke, and the cherry glow of rocks. The cherry trail followed his path, reddening rocks and sand as it passed over them. Trace darted behind the granite and raced to his lifeboat. His fingers touched the controls in flashing movements, and his eyes saw the indicators and dials without conscious thought. He kept the boat low, close to the ground, dodging in and out of the bases of the cliffs and chimneys of rock, and after a mile, he raised the nose of the craft and headed north again.

  The robot had taken eighteen hours to cross the ninety miles he had put between them. Its laser had reached out two miles to disintegrate Duncan. It had registered on his radiation detector at a distance of four miles. It had turned from its purpose of repairing the dinghy to that of destroying the men who had followed it to the planet.