Not to mention that Fischer never fought back. She keeps the insight to herself.

* * *

Concentric circles, glowing emerald. Beebe Station sits on the bullseye. Intermittent blobs of weaker light litter the display: fissures and jagged rock outcroppings, endless muddy plains, the Euclidean outlines of human machinery all reduced to a common acoustic currency.

There's something else out there too, part Euclid, part Darwin. Clarke zooms in. Human flesh is too much like seawater to return an echo, but bones show up okay. The machinery inside is even clearer, it shouts at the faintest sonar signal. Clarke focuses the display, points at a translucent green skeleton with clockwork in its chest.

"That him?" Caraco says.

Clarke shakes her head.

"Maybe it is. Everyone else is—"

"It's not him." Clarke touches a control. The display zooms back to maximum range. "You sure he's not in his quarters?"

"He left the station seven hours ago. Hasn't been back since."

"Maybe he's just hugging the bottom. Maybe he's behind a rock."

"Maybe." Caraco sounds unconvinced.

Clarke leans back in her chair. The back of her head touches the rear wall of the cubby. "Well, he's doing his job okay. When he's off shift he can go wherever he likes, I guess."

"Yeah, but this is the third time. He's always late. He just wanders in whenever he likes—"

"So what?" Clarke, suddenly tired, rubs the bridge of her nose between thumb and forefinger. "We don't run on dryback schedules here, you know that. He pulls his weight, don't fuck with him."

"Well, Fischer was always getting shit for being l—"

"Nobody cared if Fischer was late," Clarke cuts in. "They just— wanted an excuse."

Caraco leans forward. "I don't like him," she confides.

"Acton? No reason you should. He's psycho. We all are, remember?"

"But he's different, somehow. You know that."

"Lubin nearly killed his wife down at Galapagos before they assigned him here. Brander's got a history of attempted suicide."

Something changes in Caraco's stance. Clarke can't be sure, but the other woman's gaze seems to have dropped to the deck. Touched a nerve there, I guess.

She continues, more gently. "You're not worried about the rest of us, are you? So what's so special about Acton?"

"Oh," Caraco says. "Look."

On the tactical display, something has just moved into range.

Clarke zooms in on the new reading; it's too distant for good resolution, but there's no mistaking the hard metallic blip in its center.

"Acton," she says.

"Um...how far?" Caraco asks in a hesitant voice.

Clarke checks. "He's about nine hundred meters out. Not too bad, if he's using a squid."

"He's not. He never does."

"Hmm. At least he seems to be beelining in." Clarke looks up at Caraco. "You two are on shift when?"

"Ten minutes."

"No big deal. He'll be fifteen minutes late. Half hour tops."

Caraco stares at the display. "What's he doing out there?"