It was coming again.

I stayed upright in my hibernation pod, eyes shut tight. As usual, I did my best to relax, but there's not much you can do about adrenaline. Raw terror coursed through me. My mouth dried instantly, and I could taste tin. Even down at my sides, I could feel my hands shaking; my knees were locked or they'd be doing the same. I clenched my fists and relaxed them, then concentrated on slowing my breathing. In, hold, out. In, hold, out.

I could hear the medbot approaching through the darkened medbay, the click-groan of its limping steps, metal feet on rubberized metal deck plates. It paused in front of one monitor, then another, drawing ever closer, the click-groan growing louder. In, hold, out.

It stopped.

Right in front of my pod.

I willed myself to remain still. Running would be useless; there was nowhere to go. In, hold, out. The tiniest movement could give me away, so I focused on anything else — tech specs, the memory of a hillside picnic, the smell of pumpkin pie. In, hold, out.

A droplet of sweat rolled down from my hairline in defiance of the chill dry air. I prayed the machine wouldn't notice, or... what? Chalk it up to condensation? Anything but realize I was awake.

Slowly, the sweat coursed down my forehead, then onto the bridge of my nose. In, hold, out. It sat there a second, growing, then slid down to just above my right nostril. I had the insane urge to rub it away.

Suddenly, I felt the cold pressure of a metal finger. The medbot was wiping away my sweat! In, hold, out!

I think it was terror as much as anything that kept me from leaping out of my skin. I was frozen. I must not even have twitched, because a moment later I heard the click-groan again. It was moving on down the row, checking the other pods.

I must have passed out, because I'm not sure when it left the room.

* * *

We were supposed to have medcrew present when we got defrosted from cold sleep. I don't know what happened to ours, but when I woke up I was alone, cold and naked on a steel slab. There's a survival blanket in each pod, so I crawled back in, curled up in the bottom, and huddled there until I dozed off.

When I woke up, another crewman was looking in. I jumped, startled, and so did he.

"My God! You're alive!" he said.

"Last I checked. Where's everyone else?"

He shook his head. "All dead or asleep. The medbot's malfunctioning. Whenever someone comes out of hibernation, it drags them to the airlock and ejects them into space."

"That's terrible! We've got to do something!"

"Nothing we can do," he said. "The programming is locked behind a secure seal. Only the captain or a medical officer can change it. I've tried..."

His voice broke. A tear rolled through the grime on his seamed and stubbled face. Then he shook his head and returned to the present.

"Right. First things first: We'll get you a jumpsuit, and I'll show you the food and water. I've made weapons, but I don't know if even both of us working together can disable that thing."

* * *

His name was Taylor. He got me fed and clothed and then showed me around the cryo bay, taking special care to avoid the charging station where the defective medbot rested between its rounds.

It's strange how big a difference being dressed made in my mental state. Naked meant afraid, but with coveralls I felt more like myself. With a weapon in my hand, even a crude club, I was suddenly confident. Taylor noticed and shook his head dubiously.

"I dunno, man," he said. "Against a robot, what good can we do?"

"Knees," I replied. "If we can take out its legs, we'll slow it down enough that we can bash it until it stops for good. We'll need to hit it from ambush, both of us at once, and each strike a different leg."

Taylor eventually, dubiously, agreed, and just before its next scheduled rounds we took up ambush positions at the first cross corridor. The thing activated right on time, and when it got to the intersection we were ready. We both swung at the same moment, and we hit our targets: the vulnerable knee joints. Taylor's club did serious damage. Mine shattered into splinters.

The bot grabbed him and his club, one in each hand, and limped to the airlock. Without a weapon, there wasn't a single damn thing I could do. I froze, thinking furiously... and then something inside me broke.

I hurried back to my pod and climbed in. It was the only thing I could think of. I shut my eyes and waited for the inevitable.

It walked right up to me and scanned, but somehow my closed eyes fooled it. After a minute it went back into its charging bay, one leg dragging behind it.

It took me twenty minutes to force my eyes back open.

* * *

I have dreams now about waking up to see it staring back at me. When I wake for real, it often takes me an hour to open them and look around. The other day I just stayed there until it finished its next rounds. I might do that again. It's safer.

I've replaced my club with something better, a heavily weighted length of pipe. Just in case, I've made spares. Now I wait for the next crewman to wake. But it's been weeks, and I'm losing hope.

If you read this message, you'll know it's got me. There's water and a food dispenser in the nurse's cubicle, and the clubs are in the uniform locker. You know what you have to do.

And for the love of God, be careful when you open your eyes.