So why is it still “Lieutenant Markov” and “Miss Caine”?

More than that—if Paul is here, in my life, why am I with Theo?

Our home turns into a makeshift physics lab, which for me is nothing new. But my parents aren’t as warm and welcoming in this universe. Not that they’re unfriendly to Paul or anything; everyone is almost excruciatingly polite as they work. But the warmth my parents showed to Paul from the very beginning, the affection that led them to bake his birthday cake and buy him a decent winter coat—in this dimension, I see no sign of that. Maybe this is the difference between a university setting and the military. The professors who would befriend you in a graduate program have to keep their distance when they’re your superior officers.

While they’re crunching numbers, I’m left with nothing to do. Word comes that the munitions factory where I work was destroyed in the air raid, which is an enormous relief. Me building bombs? That would’ve been a recipe for disaster. The way Dad tells me this, it’s obvious he expects me to receive another duty assignment soon. But “soon” is not “today,” so my day is my own.

Normally, I spend any free time in a new dimension searching for background information. That means web pages or other, more sophisticated sources in universes that have developed that far; in universes not quite so far along, I turn to books. Mom and Dad almost always have plenty lying around, because they’re curious about everything from the ancient Incas to origami. In this world, however, it seems that paper is rationed as strictly as everything else. No encyclopedias or histories are to be had. My parents own only a handful of books, most of them novels. Even reading those might tell me something—but would I be able to figure out what’s true and what’s fiction in each one? So instead of obtaining vital facts for my mission, I wind up reading a Jane Austen novel called The Brothers. I don’t think we have that one in my universe, though, so at least that’s something.

Late in the afternoon, as they’re taking a break for a fairly depressing snack of canned peaches, my mother draws me aside. “You’re not ill at ease, are you?”

“Um, no?”

“I realize how awkward the situation is for everyone involved,” Mom continues. “Lieutenant Markov is essential to our work, and we have to work at home today, so there’s no way around it.”

She seems to expect a response. “Okay.”

“He’s handling his disappointment well, really. That’s all we can ask. I just hope it doesn’t put you in a difficult position.”

It sounds like Paul tried to get me to go out with him and I said no.

Why would I say no?

“It’s all right,” I say to her. “Paul’s a good guy. I know he’ll always do the right thing in the end.”

Mom stares at me like I just told her ostriches orbit Pluto. Is it because I slipped up and called him Paul? After a moment, though, she nods. “Sometimes I forget how insightful you are.”

I hug her, remembering the long weeks when I was trapped in dimensions where she was already dead. Traveling through the worlds gives you perspective. It makes you value what you have.

Just at nightfall, while the ad hoc scientific conference is still under way, the doorbell chimes again. Dad answers before I can. “Why, Private Beck. I don’t think I’ve seen you in ages.”

“Good evening, sir. Is Marguerite at home?” Theo catches sight of me and lights up like sunrise. He’s playing his role in this universe a little too well.

Still, the roles have to be played. “Theo,” I say as I go to him. He pulls me into his arms, an embrace so fervent, so intimate, that I can’t deal with the fact that my parents are watching this. In Theo’s ears, I whisper, “That’s enough.”

“For now,” he says in a low voice.

This isn’t my Theo.

The Theo from this universe—the one who’s been to bed with Marguerite, the one who loves her—that’s who’s holding me now.

I manage to part us without actually shoving him against the wall. My parents studiously stare down at their equations. From his chair, Paul watches us, then ducks his head when he realizes I’ve seen him.

“How did the telemetry systems fare in the raid, Private Beck?” My mother asks him this without ever looking up from her work.

“Very well, Dr. Caine,” Theo says. Huh, so my parents got around to getting married in this universe. Good to know. “In the first rush—for a moment, it felt as though I didn’t even remember how I’d gotten back to base. Strange.”

That’s because my Theo was in charge during that trip; this Theo’s consciousness didn’t reclaim his body until afterward. He must have spaced out the reminders like I told him to.

“We didn’t take too much damage,” Theo continues. “I’ve reviewed the entire system. We’ll be back to full capacity by tomorrow.”

“Have you eaten dinner?” Mom says. She’s being a bit cool—probably because she remembers us running out of the house half-dressed last night. “I can’t offer you much beyond cheese on toast, because we’re at the low end of our rations. But it’s yours if you want it.”

“I ate already. Just wanted to talk with Marguerite for a bit.”

Dad waves us off. “Fine. Go on out back.”

Out back? Theo seems to know what this means, though; he takes my hand and leads us toward the rear of the house. As we go, Paul watches us, his gray eyes yearning—no. Hungry. Then he sees my mother looking at him, and returns his attention to the papers on the table.

I love our back deck at home, with its silly tropical-fish lights and the yard that slopes so sharply you can’t even set up a lawn chair. I love the way it’s ringed by tall trees, making it seem as though our house in the Berkeley Hills isn’t crammed into an overpopulated neighborhood; instead, I feel like we’re cut off from the rest of the world, in a quiet, peaceful place of our own.

In this dimension? No such luck. We have no back deck, only the one tree. Instead, there’s a few inches of concrete that has to count as a patio, and one rickety bench. But from the way Theo pulls me down next to him on that bench, this must be our favorite place.

“I missed you today,” he whispers, and he draws me close.

My whole body flushes, but I manage to hold him back. “Wait.”

When I pull the Firebird from his uniform jacket, Theo stares. “What the hell is that?”

“You’ll see,” I say, punching in the sequence that will activate a reminder.

The charge jolts him. Theo swears under his breath and pushes himself away from me. After a couple of deep breaths, his eyes go wide. He’s my Theo again. “Whoa.”

“Are you all right?”

“I was like—I was in my body, but I wasn’t. Like sleepwalking while you’re awake. That is the weirdest thing I have ever—ever—wow.” Theo shakes his head, as if trying to clear it. “How do you deal with this?”

“It doesn’t happen to me,” I remind him. “I’m always in control, no matter what world I’m in.”

“Nice work if you can get it.” Theo takes a deep breath, then refocuses. “What exactly happened inside?”