The vault light had gone the flat amber of a system at rest. No hunt in it now, no reader combing the salt off their skin. Just the low breath of the filters and the precursor sealed behind its glass, quiet as a held tongue.
Mira looked at the seam where the lift had swallowed Fane, and counted filter cycles, because counting was cheaper than the alternative.
"You've stopped talking," Gideon said. "You do that when the answer is worse than the question."
"I do that when the question is beneath answering."
He didn't argue. He crossed the small floor and took her left wrist, where the reader in the descent had scored a line across the back of her hand, a burn gone the ugly white of denatured protein. He turned it toward the light without asking.
"Two centimeters," she said. "Superficial. It'll re-epithelialize."
"It'll scar." He tore a strip from the inner liner of his sleeve — the decontamination weave, the only clean cloth between them — and began to wind it around the burn. He worked from the wrist out, even tension, the way a man ties off a line he means to trust with weight. And he did not look at her face while he did it.
That was the thing. Not the binding. The not-looking.
She had spent three years watching Gideon Holt read rooms — the lie in a manifest, the tell in a witness who blinked on the wrong syllable. He looked at everything. Except now, with her hand open in his, he kept his eyes on the work, because he understood that if he looked up she would close like a valve, and he wanted the hand more than the flinch. It was a small, exact mercy, and she could not find the leverage in it, and that was what she could not stop turning over.
"Fane gave us a route," he said, still winding. "You know that."
"He gave us a sentence with a trapdoor in it."
"A second source witness." He tied the strip off, and then he looked up. "Is there one?"
The narrow question. The one he'd been building the whole time, foundation first, then the load.
"There's the vault telling you I made the tandem chemistry," she said. "You were beside it when it said so."
"That's not a no."
"It's the record. You put your hand on it yourself."
He held her gaze for the length of a cycle. Then he let the wrist go, and the stillness came down over his face — the quiet he used instead of anger, because anger would have cost him accuracy.
The inner door unsealed at their credential, one sound now, one green line, the two of them read as a single throat clearing. In the antechamber Anika sat against the wall with her ruined lattice cradled in her lap like something she'd hit with a car. Tovan stood over her, talking, because Tovan talked the way other people bled.
"—so I said, you can't run a decon route at forty percent flow, the biofilm laughs at you, and he says that's above my clearance, and I said congratulations, so is dying—" He stopped when he saw her. His grin held. His hands did not. "There she is. You go into the scariest room in the tower and come out looking constipated. Did it not have snacks?"
Anika didn't look up. "Did the precursor reseal?"
"Yes," Gideon said.
"Then the membrane's inert, which we knew, which means the separation reference closed inside it, which means Fane came down to pull it before it sealed and you beat him to it." She lifted her head at last, bright and merciless. "Which means the authorized procedure is gone. So how did he leave sounding like he'd won?"
The room turned toward Mira. Even Anika's silence turned; she had a gift for it, a way of stopping mid-sentence so the quiet did the asking.
"He offered a substitute," Mira said, in the register she used for reporting yields. "A second living source witness. Grow a reference from their skin instead of the sealed one. If such a person existed."
"Does one?" Anika said.
Tovan laughed, one note, wrong-shaped. "Mira worked alone. She's told me that every family dinner for ten years. I did it alone, Tovan. Stay out of it, Tovan." He said it lightly, and his hands were fists now, jammed into the coverall pockets. "Right?"
And there it was, the whole trap, standing in maintenance grey with a chemical burn on the web of his left thumb.
She knew that burn. She had its twin under the fresh dressing on her own hand — older, silvered, from the same night. The first scaffold. A borrowed glovebox on the sixty-third floor, him fifteen and furious and better at the fold than she'd ever admitted, his hands in the box beside hers because no one could lay a tandem lattice alone. That was the point. That was why it was called tandem. Two hands, two signatures folded into one lattice at the origin.
She had spent two years scrubbing his name out of every log that survived. She had let him believe she resented his help so he would stop offering it. She had built her whole silence around the fact that somewhere in this tower there was one other set of skin that could be grown into the reference the vault had just eaten, and it belonged to her brother.
"No," Mira said. "There was no one else."
Beside her, Gideon went very quiet.
He knew. She'd watched him take apart people who lied better than she just had. He knew the way the sentence had come out one beat too smooth, the way she'd chosen no one instead of nobody, the way she had not looked at Tovan while she said it — the same trick he'd used on her hand a minute ago, and he'd have recognized it as his own.
He said nothing.
He, who had spent three years and his entire record hunting the falsified inside true-sounding sentences, stood in a resealed vault and let her false one hang in the air untouched. He didn't correct it for Anika. He didn't turn it over for Tovan. He absorbed it the way he'd absorbed the strip of his own sleeve, and she understood that he had chosen again, without being asked, to make her lie his own.
She should have felt safe. She felt watched, and wanted, and cornered by the one kind of attention she had no defense against, which was patience.
Anika found a reason to take Tovan to the flow gauge in the outer corridor. When their voices had moved off, Gideon spoke without turning his head.
"You have the name."
"I have a headache."
"I'm not going to make you say it." He watched the sealed precursor through the inner glass, that flat amber, the thing they'd signed shut together with four hands and one file. "I want you to understand the arithmetic first. My individuation index is gone. You watched it burn. The only clean reference for the authorized separation is behind that glass, and neither of us can open it again without ending up inside it." The pause he used to let a load settle. "If there is no second witness, we are one identity until the archive dies. My record stays fused to yours. I stay a man whose innocence can't be proved, because there's no longer a version of me clean enough to prove it. And you—"
"And I keep my freedom the way a fish keeps water," she said. "I'm aware of the arithmetic. I did it before you learned to spell it."
"Then you already know that saying nothing chooses this. For both of us." He looked at her at last, and there was no accusation in it, which was worse. "I only wanted to be sure you knew you were choosing."
He'd done it again — laid the decision in her open hand and tied it off, even tension, and refused to make it for her. It would have been kinder to grab it. She could have hated a man who grabbed.
Tovan came back with a flow reading he didn't need and a joke half-loaded. Mira met him at the door.
"Go up," she said. "Log the descent as a false alarm, sign the flow drop off as biofilm, and stay off the security floor until I send for you."
The joke went out of him like heat off metal. "I just spent an hour outrunning a lethal reader for you—"
"And it's the last thing I'll ask." She made her voice the flat white of the burn under the dressing. "You cooked a decon override you weren't licensed to write to get me down here. If the Directorate reads the route, they read you. So bury it. Stay small. And stop trying to repay a debt I never opened."
It landed exactly where she aimed it. His hands stopped shaking, which was how she knew she'd hit something true — Tovan went still and formal only over the things worth lying about. "Fine," he said. "Sure. Alone, then. Like always."
He turned the burned thumb over on the door plate to key it, and did not see her look at it. The door took his single, ordinary signature and let him through.
Gideon watched the seam close. Then he watched her, and asked the only narrow question he had left.
"How long have you known your brother's skin is the reference?"