“Un, deux, trois …” calls a playful voice behind me. A familiar voice. Thomas.

The voice is coming from the front of the train. Along with an eerie red glow.

I step down from the train onto the tracks, squinting down the line of cars.

“Thomas Alain Laurent!” I shout. “Come out, come out, wherever you are.”

The red light dances along the tunnel wall, and I can hear the shuffle of small feet. A soft giggle. I clutch the pendant as I creep down the side of the train car.

But he doesn’t show himself.

Maybe Lara was right; maybe the name isn’t enough.

“Thomas, please,” I call, and then, mustering my only French, “S’il vous plaît.”

The red light brightens, shining along the tracks, and I see a pair of red eyes peek between cars. I hold out my hand, the way Thomas did on the street last night, an invitation to come play.

Thomas smiles.

And then he presses his small hands to the side of the train. The crimson light ripples out from his fingers, and then he giggles again, and disappears.

“No,” I hiss, jerking forward, but Jacob grabs my arm.

“Cass.”

“What?” I snap, twisting free.

“The train.”

And I don’t understand what he means until I hear it.

A faint and far-off groan. The sound isn’t human.

It’s metal.

And it’s coming from the other side of the Veil. The power is back on. The train is starting up again.

I lurch toward the gap between cars as the ghostly train creeps forward. Jacob gets there first, hauls himself up, and offers a hand, and I’m grateful that he’s solid enough for me to take it.

He pulls me up just as the train begins to gain speed, and I throw open the door, and the Veil with it, stepping back into the real world as the lights flicker on around us.

Pauline sees me through the crowd and frowns as I weave my way toward her.

“There you are,” she says, grabbing my shoulder.

Her eyes are wide, her face pale, her other hand clutching the pendant at her chest. And I realize it’s the first time I’ve seen her truly lose her composure. The first time I’ve seen her mask of calm slip, reveal the thing beneath: fear.

Pauline is terrified.

“You’re not a skeptic, are you?” I say.

She lets go of my shoulder and forces out a steadying breath. “I don’t know what you’re talking about.”

I narrow my eyes. “You’re not just superstitious. You’re a believer.”

Pauline bristles. “No, of course not.”

But the no is too quick, too forceful.

“What are you ashamed of?” I ask. “You’re with a group of people whose whole job is to believe in ghosts.”

“I’m not ashamed of anything,” she retorts, folding her arms across her chest. “I don’t want to believe in ghosts.”

“But you do.”

She sighs. Hesitates. “What was it you said? It is easy not to believe, and then once you experience something, it’s hard not to?”

The train pulls into the station.

“I have … seen things, once or twice. Things I could not explain.” Pauline shakes her head as the doors slide open. “Mon dieu, I sound like a fool.”

I shrug. “Not to me.” She manages a small, tight-lipped smile, then shoos me off the train onto the platform.

It seems busy, even busier than usual. People are muttering under their breaths and clustering in front of electronic signs that show the different Metro lines, red warnings popping up beside them. First one, then two, then four.

“What’s going on?” I ask.

“It looks like our train is not the only one having trouble,” says Pauline.

“There’s no way Thomas could be doing all that,” says Jacob. He looks at me, a little nervous. “Right?”

I want to believe him. But I don’t. The warnings flash, bright red, and all I can see are the poltergeist’s eyes, the way the crimson seemed to spread out into the air around him.

First comes mischief, then comes menace, then mayhem.

The more trouble poltergeists cause, the more powerful they get.

We have to hurry.

I turn to Pauline, holding out the address for Sylvaine Laurent. “Lead the way.”

“Tell me, Cassidy,” says Pauline as we walk. “Why are you so interested in this family?”

“Mom says I’ve always been naturally curious.”

She raises a brow. “Is that all? Or is there another reason you wish to visit the Laurents?”

I shift my weight from foot to foot. “Do you really want to know?”

Pauline seems to genuinely consider it. “No, I think not,” she says, then sighs. “But you should probably tell me anyway.”

So, I do.

I tell her about ghosts and poltergeists, about the fact that I somehow woke one poltergeist up and now it’s following me, causing all kinds of trouble.

Pauline blinks, her hand drifting to the charm around her neck. “And the Laurents … ?”

“They’re the poltergeist’s family,” I say. “I’m hoping if I learn what really happened to Thomas, it will help me send him on.”

Pauline starts to speak, but an emergency vehicle whips past, sirens wailing. She waits for them to fade, then starts again.

“And why is it your job to send this spirit on?”

“That’s a great question!” says Jacob, but I ignore him.

“I guess because I can. A year or so ago, I almost died, and now I can cross the Veil—that’s the place between this world and the one with the ghosts—and my friend Lara says it’s kind of like paying back a debt.”

“That seems like a lot of pressure for a girl so young.”

“Oh, I don’t have to do it alone,” I say. “I have Jacob.”

She raises a brow. “Jacob?”

“He’s my best friend,” I say, adding, “He’s a ghost.”

This time both eyebrows go up. “I see.” And despite what she just said about believing, I can tell she doesn’t believe me.

When I tell her that, she sighs. “I believe that you believe.”

I shake my head. “Why is it that when kids believe in something, adults write it off as imagination, but when adults believe in something, people assume it’s true?”

“I’m not sure anyone would assume this is true.”

“But you just said you’ve seen things. You said you believed.”

Pauline shakes her head. “Belief is not a blanket, Cassidy. It doesn’t cover everything. Forgive me. There’s a big difference between believing in the supernatural in the general sense and believing the twelve-year-old girl you’re escorting across Paris is a ghost hunter with a dead sidekick.”

“Excuse me,” says Jacob. “Who is she calling sidekick?”

Before I can explain that he’s more of a partner in crime, Pauline stops, gesturing to a lemon-yellow building with white accents and flower baskets in the windows. “Here we are.”

It’s an old-fashioned apartment building. Lara didn’t give me an apartment number, but a quick scan of the buzzers running down the right side says that “Mme Laurent” lives in 3A. A man is walking out of the building, and I catch the front door before it can swing closed behind him. Pauline and I slip inside.