"Tweaked." The word lies thick and dead in the space between them.

Rowan forces herself to continue. "To adapt it to aerobic environments. And to increase its reproductive rate, for faster production. There were commercial applications. Nobody was trying to bring down the world, of course, it wasn't a bioweapons thing at all…but evidently something went wrong."

"Evidently." Clarke's face is an expressionless mask.

"I'm sure you can see the danger here, if your people stumble across these modifications without really knowing what they're doing. Perhaps they know enough to recognize a tweak, but not enough to tell what it does. Perhaps they don't know how to tell old tweaks from more recent ones. Or perhaps the moment they see any evidence of engineering, they'll conclude the worst and stop looking. They could come up with something they thought was evidence, and the only ones qualified to prove them wrong would be ignored because they're the enemy."

Clarke watches her like a statue. Maybe the reconciliation of the past few years hasn't been enough. Maybe this new development, this additional demand for even more understanding, has done nothing but shatter the fragile trust the two of them have built. Maybe Rowan has just lost all credibility in this woman's eyes. Maybe she's just blown her last chance to avoid meltdown.

Endless seconds fossilize in the cold, thick air.

"Fuck," the rifter says at last, very softly. "It's all over if this gets out."

Rowan dares to hope. "We've just got to make sure it doesn't."

Clarke shakes her head. "What am I supposed to do, tell Rama to stop looking? Sneak into the hab and smash the sequencer? They already think I'm in bed with you people." She emits a small, bitter laugh. "If I take any action at all I've lost them. They don't trust me as it is."

Rowan leans back her seat and closes her eyes. "I know." She feels a thousand years old.

"You fucking corpses. You never could leave anything alone, could you?"

"We're just people, Lenie. We make…mistakes…" And suddenly the sheer, absurd, astronomical magnitude of that understatement sinks home in the most unexpected way, and Patricia Rowan can't quite suppress a giggle.

It's the most undignified sound she's made in years. Lenie arches an eyebrow.

"Sorry," Rowan says.

"No problem. It was pretty hilarious." The rifter's patented half-smile flickers at the corner of her mouth.

But it's gone in the next second. "Pat, I don't think we can stop this."

"We have to."

"Nobody's talking any more. Nobody's listening. Just one little push could send it all over the edge. If they even knew we were talking here…"

Rowan shakes her head in hopeful, reassuring denial. But Lenie's right. Rowan knows her history, after all. She knows her politics. You're well past the point of no return when simply communicating with the other side constitutes an act of treason.

"Remember the very first time we met?" Lenie asks. "Face to face?"