Page 27

"It's a two-man job," Claire says, staring at it. "That's the design philosophy. It isn't testing whether you're clever. It's testing whether you can be clever in two directions at once."

"Precision and improvisation."

"One of each. Neither alone." She laughs, and it has an edge on it. "Somebody built a city that can only be run by two people who disagree productively. The most insane engineering decision I've ever met, and I'd like to shake their hand."

Beyond the node is the answer to a question I carried my whole career without knowing it.

Transit corridors. Not the spine — the spine is one artery. These are capillaries, hundreds of them, and they go everywhere. All nineteen districts. Vaulted runs three meters by four, clean, lit, threading under the foundation rafts of the whole city and terminating in risers that surface inside plant rooms I have personally worked in.

I have stood in those rooms. I have looked at those blank walls. In my fourth year I filed a request asking why a Founders' Sixth plant room had a sealed alcove on its north side, and the answer came back: structural fill.

It isn't fill. It's a doorway, and behind it is a road, and the road has been there a hundred centuries.

"It was never maintained from above," I say, out loud, to nobody. "Not once. Every plant room on this planet is a service hatch. This city has always been maintained from below, and we built a civilization on top of the ceiling and called ourselves engineers."

Claire comes and stands next to me and says nothing, which she has learned to do and which I did not teach her.

We sleep in the Cistern that night because it's closer than the surface, and afterward, on that miserable damp shelf, she says something into my shoulder I have to ask her to repeat.

"I said, what happens to us when this ends."

"The assignment ends on day forty-two."

"I know when it ends. That isn't the question."

I study the vaulted brick. Her hand is on my chest, my markings are lit under it, and no version of this conversation can be had carefully.

"Among my people we don't ask that," I tell her. "Jalshagar isn't a decision, and asking what comes next implies a next in which it isn't happening. There is no such next. There is only whether the two people involved are honest about it."

"Restful for you. I have a Coalition contract and a return berth."

"Yes."

"Darius."

"Cancel the berth," I say.

She is quiet long enough that I begin composing an apology.

"Okay," she says. "But I'm renegotiating, because if I'm staying I want hazard pay, a real office, and never this bunk again."

"It's the best bunk in the station."

"It's a wet shelf and you've always known."

I have always known. Nineteen years of knowing. I let her have the last word, which is a thing I am learning to do, and above us the city breathes on machinery it has never once thanked.

CHAPTER 15

CLAIRE

Ifind the first one because of the oxide.

Day thirty-six, and I have become the kind of person who checks welds. The bracket in the inspection void has fifteen years on it, and fifteen years means somebody had a route, and a route means somebody had support, and support leaves things behind. So I go looking for what got left behind.

It takes four hours. It's in the rock gallery outside the gate, tucked up under the shoring beam Darius placed eleven years ago, and it is no bigger than my thumb.

A transmitter. Surface manufacture, commercial parts, nothing military — the kind a contractor uses to monitor plant conditions somewhere nobody visits. Sixteen months of power left.