Something sits hunched at the main workstation, running a sequence of rainbow nucleotides. It can't be a rifter. It doesn't have the affect, it doesn't have the black shiny skin. It looks more like a hunched skeleton in shirtsleeves. It turns, and Clarke flinches inwardly: it doesn't even have the eyes. The pupils twitching in Bhanderi's face are dark yawning holes, dilated so widely that the irises around them are barely visible.

Not so bright, then. Still dark enough for uncapped eyes to strain to their limits. Such subtle differences get lost behind membranes that render the world at optimum apparent lumens.

Something must show on her face. "I took out the caps," Bhanderi says. "The eyes— overstimulate, with all the enhancers." His voice is still hoarse, the cords still not reacclimated to airborne speech.

"How's it going?" Clarke asks.

A bony shrug. She can count the ribs even through his t-shirt.

"Anything yet? Diagnostic test, or—"

"Won't be able to tell the difference until I know if there is a difference. So far it looks like ßehemoth with a couple of new stitches. Maybe mutations, maybe refits. I don't know yet."

"Would a baseline sample help?"

"Baseline?"

"Something that didn't come through Atlantis. Maybe if you had a sample from Impossible Lake, you could compare. See if they're different."

He shakes his head: a twitch, a tic. "There are ways to tell tweaks. Satellite markers, junk sequences. Just takes time."

"But you can do it. The—enhancers worked. It came back to you."

He nods like a striking snake. He calls up another sequence.

"Thank you," Clarke says softly.

He stops.

"Thank you? What choice do I have? There's a lock on the hatch."

"I know." She lowers her eyes. "I'm sorry."

"Did you think I'd just leave? That I'd just swim off and let this thing kill us all? Kill me, maybe?"

She shakes her head. "No. Not you."

"Then why?"

Even motionless, his face looks like a stifled scream. It's the eyes. Through all the calm, rapid-fire words, Bhanderi's eyes seem frozen in a stare of absolute horror. It's as if there's something else in there, something ancient and unthinking and only recently awakened. It looks out across a hundred million years into an incomprehensible world of right angles and blinking lights, and finds itself utterly unable to cope.

"Because it comes and goes," Clarke says. "You said it yourself."

He extends one stick-like forearm, covered in derms; a chemical pump just below his elbow taps directly into the vein beneath. He's been dosing himself ever since he climbed back into atmosphere, using miracles of modern chemistry to rape sanity back into his head, to force submerged memories and skills back to the surface for a while. So far, she has to admit, it's working.

But whenever she looks at him, she sees the reptile looking back. "We can't risk it, Rama. I'm sorry."

He lowers his arm. His jaw clicks like some kind of insect.