gone in this direction, and I doubted Pickover had, either.
A rat scampered out of our way, squealing as it did so. My breathing was already ragged, but I managed to say, “How well can you guys see in the dark?”
Pickover’s voice, of course, showed no signs of exertion. “Only slightly better than biologicals can, unless you specifically get an infrared upgrade.”
I nodded, although he’d have needed better vision than he’d just claimed in order to see it. My legs were a lot longer than Cassandra’s, but I suspected she could pump them more rapidly. I swung the flashlight beam up, letting it lance out ahead of us for a moment. There she was, off in the distance. I dropped the beam back to the floor.
More splashing from up ahead; she’d veered off once more. I thought about firing a shot—more for the drama of it than any serious hope of bringing her down—when I suddenly became aware that Pickover was passing me. His robotic legs were as long as my natural ones, and he could piston them up and down at least as quickly as Cassandra could.
I tried to match his speed but wasn’t able to. Even in Martian gravity, running fast is hard work. I swung my flashlight up again, but Pickover’s body, now in front of me, was obscuring everything farther down the corridor; I had no idea how far ahead Cassandra was now—and the intervening form of Pickover prevented me from acting out my idle fantasy of squeezing off a shot.
Pickover continued to pull ahead. I was passing open door after open door, black mouths gaping at me in the darkness. I heard more rats, and Pickover’s footfalls, and—
Suddenly something jumped on my back from behind me. A hard arm was around my neck, pressing sharply down on my Adam’s apple. I tried to call out to Pickover but couldn’t get enough breath out . . . or in. I craned my neck as much as I could, and shined the flashlight beam up on the ceiling, so that some light reflected down onto my back from above.
It was Cassandra! She’d ducked into one of the other rooms and lain in wait for me. Pickover was no detective; he had completely missed the signs of his quarry no longer being in front of him—and I’d had Pickover’s body blocking my vision, plus the echoing bangs of his footfalls to obscure my hearing. I could see my own chilled breath but, of course, not hers.
I tried again to call out to Pickover, but all I managed was a hoarse croak, doubtless lost on him amongst the noise of his own running. I was already oxygen-deprived from exertion, and the constricting of my throat was making things worse; despite the darkness I was now seeing white flashes in front of my eyes, a sure sign of asphyxiation. I only had a few seconds to act.
And act I did. I crouched as low as I could, Cassandra still on my back, her head sticking up above mine, and I leapt with all the strength I could muster. Even weakened, I managed a powerful kick, and in this low Martian gravity, I shot up like a bullet. Cassandra’s metal skull smashed into the roof of the corridor. There happened to be a lighting fixture directly above me, and I heard the sounds of shattering glass and plastic.
I was descending now in maddeningly slow motion, but as soon as I was down, Cassandra still clinging hard to me, I surged forward a couple of paces then leapt again. This time, there was nothing but unrelenting bulkhead above, and Cassandra’s metal skull slammed hard into it.
Again the slow-motion fall. I felt something thick and wet oozing through my shirt. For a second, I’d thought Cassandra had stabbed me—but no, it was probably the machine oil leaking from the bullet hole I’d put in her earlier. By the time we had touched down again, Cassandra had loosened her grip on my neck as she tried to scramble off me. I spun around and fell forward, pushing her backward onto the corridor floor, me tumbling on top of her. Despite my best efforts, the flashlight was knocked from my grip by the impact, and it spun around, doing a few complete circles before it ended up with its beam facing away from us.
I still had my revolver in my other hand, though. I brought it up and by touch found Cassandra’s face, probing the barrel