“Be careful when you go through the process,” he says, clicking my Firebird back into its proper configuration, all the thin metal layers folding in on one another like an insect’s wings. “We built this thing to be easy to repair and customize, so when you have it all spread out like that, it can pop apart. Simple enough to fix if you know how—but that’s something I can’t teach you in an hour. Or a month.”

“Right. It’s complicated. You don’t have to keep reminding me.”

Theo’s brown eyes meet mine, warm and knowing. “Somebody’s in a mood.”

“We’re going to kill a man. Should I be perky?”

He holds his hands up, like, I surrender. “I know this is hard, all right? It’s not easy for me either.”

Little brother. Theo used to take Paul out for what he called “Remedial Adolescence”—trying to introduce him to music and clubs and even girls, all the stuff he missed out on when he started doing higher physics at age thirteen. Of course, Theo did that partly to soak up the hero worship, because Paul thought Theo was about eighty times cooler than anyone else on earth.

Or we believed he did, anyway. In the end, Theo was as deeply deceived by Paul as the rest of us. As bitterly betrayed.

“I’m sorry.” I lean my head back against the plastic seat and stare upward at the shiny holographic ads squiggling above us, begging me to buy products I’ve never heard of. “I know I’m acting like a bitch. I’m tired is all.”

“It’s not easy,” he agrees. “We can save ‘nice’ for later. After.”

“Right.”

The monorail comes to our stop. Theo and I step out of the car side by side, without saying another word to each other. Maybe he’s still thinking that nice comes later. Maybe that’s what I should be thinking too. Instead my mind is clouded with uncertainty about what we’ll find when we see Paul, whether we’ll see him at all, and, worse, with doubts about my resolve.

I can’t even look at Theo, lest he see how worked up I am. So I glance around at the crowds rushing by us in this station of metal grids and holographic signs, hoping for a moment’s distraction from the dark work ahead.

One figure halts in his tracks. A large man in a long black coat, stopping midstep to check a holographic map of the area floating overhead. As the motion flickers in the corner of my eye, I turn toward it and my first thought is, He’s having a heart attack.

Then I see who it is.

I’ve chased Paul Markov across dimensions. Now he’s only twenty feet away.

8

I PUT MY HAND OUT, TRYING TO WARN THEO, BUT NO WARNING is needed.

“Son of a bitch,” Theo whispers.

He starts forward, but I grab his shirt in my fist. “Don’t. Theo, don’t.”

“What do you—” At first he’s angry I’ve stopped him—so angry it shocks me—but then Theo visibly relaxes. “Right. Not exactly the place for this confrontation. Probably security cameras and transit cops around every corner.”

That’s not why I stopped Theo. It’s because seeing Paul has taken me back to the first moments after I heard the police say his name, call him a suspect in Dad’s death. Bizarrely, I didn’t get angry right away; I was too dazed for anything as coherent as anger. I kept thinking that this couldn’t be right. That the horrible things I was hearing couldn’t be real.

While the police were standing in our living room, and Mom cried into her hands as they talked about Paul’s “suspicious activity,” I kept thinking I should call him, so Paul could explain what was really going on.

And right now, as I look at him, I don’t see my father’s killer. I see the Paul I used to know.

The one who made me feel like I might finally fall in love.

Thanksgiving at our house is always a little weird. We don’t have much family aside from Aunt Susannah, who seems to think Thanksgiving is some barbaric American custom that would give her the cooties. So my parents invite along a motley crew of physics students, other professors, and neighbors. The grad students always contribute a dish, and they come from all over the world, which means we might have kimchi or empanadas along with the turkey. One time Louis—who was from Mississippi—brought something called a turducken; personally I don’t think any food should have the word turd in its name, but it turned out to be a chicken stuffed inside a duck stuffed inside a turkey, and I have to admit it was delicious. The turducken was one of the better offerings, really. Sometimes they’re almost sad, like this year, when Theo brought cupcakes we all pretended hadn’t been bought from a store.

Paul asked to borrow our kitchen, because he didn’t have access to a stove. So I was there to witness him cooking. “Lasagna?” I boosted myself up to sit on the counter. “Just like the Pilgrims used to make.”

“It’s the only thing I know how to cook.” Paul frowned down at the tomato sauce in its pot, as though it had done something to offend him. “The only thing worth bringing, anyway.”

I resisted the urge to point out that if he was cooking at our house, he wasn’t precisely bringing it anywhere. We had finally reached the point where I was starting to get comfortable with him—where I was starting to believe I might be able to get beneath all the quiet and awkward to figure Paul Markov out.

Mom and Dad were at the university; Theo was out partying; Josie wouldn’t fly in from San Diego until tomorrow morning, apparently because she’d spent the day surfing with her friends. So Paul and I were alone for a change. He wore his usual faded jeans and T-shirt. (I swear it’s like he doesn’t know people are allowed to wear anything besides black, white, gray, and denim.) Yet somehow he made me feel overdressed in my tunic and leggings.