“You’re small and quick. Your best hope is to avoid the blows. If you came up against someone like me in a real fight, you wouldn’t stand a chance.” He probably weighs about half again what I do, so he has a point. It grates, but I learn.

He’s not a bad teacher. He doesn’t shout—he tells me what I do wrong, but praises what I do right. As my muscles grow more exhausted, his voice seems to hum near my ear: “Duck, left, back,” and I move almost without thinking.

Detective Nazarin calls a stop after three hours. I’m panting, but proud of myself that I kept going and didn’t ask for breaks except the odd gulp of water. Nazarin is glazed in perspiration, but strangely, he smells good. Musk and cologne and clean sweat.

“Strong start,” he says. “Soon, you’ll be better.”

Once it’s wired into my brain.

“Now,” Detective Nazarin says, “it’s time for you to legally become Tila, at least for a little while.”

*   *   *

I have enough time to shower and choke down some vat jerky and dried fruit before Detective Nazarin takes me to meet Dr. Kim Mata, a biohacker working for Sudice, Inc.

We can’t go to the Sudice headquarters: they’re the parent company of VivaFog and I’ve already told my co-workers I’ll be on a jet to China imminently, and it would compromise Nazarin’s cover. But we can’t bring Dr. Mata to the safe house. Instead we make our way down to one of her empty properties. She’s often hired by the SFPD to do these sorts of jobs, Nazarin says, but she keeps it quiet from Sudice. I’m surprised she’s able to.

Time to switch identities.

On the way there I lean against the window, my tired muscles quivering. It feels good, though, like my mind has connected better with my body now that it has that particular buzz of exercise exhaustion. I’ll take some Rejuvs when I get back, and between that and my implants, tomorrow my muscles won’t even be sore, but I’ll be that much stronger.

How much stronger do I have to be? What exactly do they think is going to happen?