In the center of the great room is our dinner table, an enormous round wooden one Mom and Dad bought for cheap at a Goodwill back when Josie and I were little. They let us paint it in a rainbow of colors, just goop it on with our hands, because they loved hearing us laugh and also because no two human beings on earth ever cared less about how their furniture looked. Josie thought it was funny to smear swirls on with her fingers. For me, though—that was the first time I noticed how different colors looked when you blended them together, contrasted one next to another. It might have been the moment I fell in love with painting.

“I guess you think painting isn’t as important as physics,” I said to Paul as I sat at my easel, that one day he watched me work.

“Depends on what you mean by important,” he replied.

I could have thrown him out right then. Why didn’t I?

My memories become dreams as I fall asleep without knowing it. All night I see Paul’s face in front of mine, staring at me, questioning me, planning something I can’t guess. The next morning, when I wake up in this cold, foreign bed, I can’t remember the dreams. I only know that I tried to go after Paul but never could move.

Surprisingly, there’s no disorientation. From the first moment I open my eyes, I know where I am, who I am, and who I’m supposed to be. I remember what Paul did to my father, that I’ll never see Dad again. As I lie there amid the rumpled white sheets, I realize how little I want to move. My grief feels like ropes tying me down.

“Come along, sweetie!” Aunt Susannah calls. “Time to make yourself pretty!”

Not unless the technology in this dimension borders on the miraculous. I sit up, catch a glimpse of my crazy bedhead curls reflected in the window, and groan.

Apparently we’re going to a “charity luncheon,” though my aunt doesn’t remotely care about whatever charity it’s for; she doesn’t even remember what it is. It’s a society event—a place to see and be seen—and that’s all that matters to Aunt Susannah.

Still, I know I have to stay put and wait for Theo. If I’m going to stop Paul, I’ll need all the help I can get—and Theo is the only one who can help me. So, for one whole day, I have to lead this Marguerite’s life.

From what I can tell, it’s not much fun.

“Come on, dear.” Aunt Susannah trips along the cobblestone street in her high-heeled shoes, as nimble as a mountain goat. “We can’t be late.”

“Can’t we?” The idea of navigating a whole social event as another version of myself—it’s pretty intimidating.

She gives me a confused glance over her shoulder. “But I wanted you to get to know the duchess. Her niece Romola is at Chanel, you know. If you want to be a fashion designer someday, you’ve got to make some connections now.”

In this reality, I want to be a fashion designer? Well, at least that’s creative. “Right. Sure.”

“Don’t pretend you’re too sophisticated to be impressed by a title,” Aunt Susannah says. She gets like this—brisk and slightly contemptuous—whenever she’s challenged. “You’re an even bigger snob than I am, and you know it. Just like your mother.”

“What did you say?”

“I know, I know, to you your parents are saints, and they should be. I’m not saying they weren’t absolutely lovely people. But how your mother used to go on about being descended from Russian nobility! You’d think she personally fled the Red Army with the Romanov jewels in her arms.”

“Her family was from the nobility. They did flee the Revolution. They were expats in Paris for the next four generations, before her parents finally moved to America. She’d never lie about being something she’s not.” Then I remember that I’m not supposed to have known my mother very well in this dimension, and that here, she’s as lost to me as my father. “I mean, she wouldn’t have.”

And Mom wouldn’t. She only cares about two things: science and the people she loves. The one who wears her crazy-curly hair twisted back with whatever pencil or pen she finds lying around. The one who let me finger paint the table. Nobody on earth is less of a snob than Mom.

We’re standing in the middle of the street now, still a block short of the hotel where the duchess and a hundred and forty of her closest friends are taking tea. Aunt Susannah puts one hand to her chest like an actress in a cheesy old movie, and yet I know she’s sincere—as sincere as she knows how to be, at least. “I wasn’t putting your mum down. You realize that, don’t you?”

From Aunt Susannah, “snob” is practically a merit badge. I sigh. “Yeah. I know.”

“Now, I’d hate for us to be cross with each other.” My aunt comes close and puts her arm around me. “It’s always been just us. You and me against the world, hmm?”

I could almost believe we had a good life together, if I hadn’t been in that impersonal apartment. Or if I didn’t see through the translucent lenses of Aunt Susannah’s sunglasses to her bored, impatient gaze.

It’s taken me less than a day to discover that Aunt Susannah resents having to play surrogate parent to this dimension’s Marguerite. What must it have been like for her to live a whole lifetime knowing that? To feel so rejected by the only family she had left in the world?

“You and me,” I repeat, and Aunt Susannah smiles like that’s a reason to be happy.

In my real home, it’s never been “just us.”