Jacob holds out his hand, and Thomas is about to reach for it. The red light in his eyes is almost gone, and I’m almost there when my knee comes down on a brittle bone—

And the bone snaps. Not enough for me to slip, but the sound rings out through the dark like a branch breaking in a silent forest.

Thomas twists away from Jacob, the red light surging back into his eyes. I cut sideways, out of his sight, and into the deeper dark.

Too late, I realize my mistake.

Too late, all my weight shifts from the stable wall to the stack of rotting bones.

Too late, and the pile gives way, crumbling like ash beneath me, and I’m falling down, down, down into the dark.

There are many kinds of dark.

There’s the warm, reddish dark you see when you close your eyes.

There’s the rich dark of a movie theater, the audience lit only by the screen.

And then there’s the true dark of lightless spaces underground, places where the black is so thick you can’t see your own hands. Can’t see the lines of your body. Can’t see any of the things you know are there with you in the dark.

This is that kind of dark.

I cough, my lungs filling with ash and soot. Something digs into my side. And for a moment, all I can think is, This is how he died. Thomas, buried by bones.

But I’m still alive.

I’m still alive.

Even if I can’t see.

And then I remember my phone. I scramble to pull it out—there’s no service down here, but I don’t need to make a call. I just need some light. I turn the phone on and activate its built-in flashlight. The world around me bursts into glaring white light. The sight is … unpleasant. I’m on my back at the bottom of the hole, the edges above me flaking with dust. I get to my hands and knees, trying to hold my breath against the plume of death and decay as I swing the phone’s light. The hole isn’t deep, maybe four feet. I can reach up, curl my fingers back over the edge, but the crumbling bones are soft in places, sharp in others. And every time I move, the air fills with things I don’t want to breathe, don’t want to think about.

“Cassidy!” calls Jacob, his voice tight with panic.

“I’m all right!” I call back.

“Well, I’m not!”

I look around, nothing but darkness on three sides, but the wall of femurs and skulls on my left. When I press my eye to the gaps, I can see Jacob, lined with red light as his arms wrap tightly around Thomas, pinning the boy back against him.

Thomas thrashes, trying to twist free. The air around him ripples and glows red, and the whole tunnel begins to shake as the crimson light spreads over everything, splitting across the floor, the ceiling, and the walls of bone.

The poltergeist is angry.

I reach up, trying to haul myself out of the hole, but I can’t get a grip. The sides of the hole slough away, dirt and dust and gritty stuff coming away in my hands. I can hear the sound of footsteps, the shuffle of feet, and I have the unsettling feeling that soon, we won’t be alone in this section of the tunnel.

“Cass!” yelps Jacob.

“Hold on!” I call back, turning in a slow circle, trying to figure out what to do. I try to wedge my shoe in a gap, but it’s no use. Up is out of the question.

The whole ground begins to shake with the force of Thomas’s displeasure. Even the wall of bones to my left begins to tremble and shift.

Dad has a saying: The only way out is through.

I slam my shoulder into the wall, feel it shudder and slip. I hit it again, biting back a jolt of pain as the whole wall bows and leans, and finally tips and tumbles.

And falls.

The tunnel fills with the shattering sound as hundreds of dry bones crash against the dirt and stone. I spill out, coughing ash, tripping as I try to wade through the shallow tide of bones.

Jacob looks at me, eyes wide, the word unspoken but clear.

Hurry.

His hair floats in the air around him, his own eyes bright, as the boy in his arms screams and twists and fights to get free.

But Jacob doesn’t let go.

I start toward them, ash dusting my skin, the mirror clenched in my hand as the walls of bone on either side sway and threaten to fall. But Thomas’s eyes are still red, the photographs whipped up and torn by the whirlwind around him.

And my heart sinks, because I’ve tried everything, and Thomas still hasn’t found his way back. Still hasn’t remembered.

I don’t know what to do.

But in the end, I’m not the one who does it.

Jacob’s arms tighten on Thomas, and he says, “C’est finit.”

I remember us back in the hotel room, sitting on the floor as Adele told the story of what happened to the brothers that night.

Richard called out, “Thomas, c’est finit”—“it’s over”—but there was no answer, except for his own voice, echoing in the tunnels.

The red light flickers in Thomas’s eyes.

The tunnel shudders, and I fight to stay on my feet. Bones crash around us, brittle as glass.

“Non,” whispers Thomas, but he no longer sounds angry. Only sad, and lost.

“C’est finit, Thomas,” repeats Jacob, and I swear I can see tears streaming down the dust on his face.

“C’est finit,” Thomas whispers back, and the red light falters and fails.

At last, Thomas stops fighting.

The tunnel stops shaking.

The Empire of the Dead goes quiet and still.

Thomas stares up at me, his eyes wide and brown and scared as I reach him. Jacob bows his head against the boy, his eyes squeezed shut as I bring the mirror up.

“Watch and listen,” I say gently.

His edges ripple in Jacob’s arms.

“See and know.”

He gazes into the mirror, tears staining his cheeks.

“This is what you are.”

Thomas thins from flesh and blood to gossamer and smoke, and I reach into the boy’s chest, fingers closing around the thread. I draw it out, the thin coil of a life that shouldn’t have been so short. It comes free, dissolving in my palm, and as it disappears, so does Thomas Alain Laurent.

There, and then gone.

Poltergeist, and then ghost, and then nothing.

Jacob’s arms fall to his sides, empty. He slumps back against the wall behind him, for once not even seeming to mind that it’s made of skulls.

“Jacob?” I whisper, worried by his silence.

He scrubs at his eyes and swallows. Then he pulls the borrowed cap from his head and tosses it aside. “Ick,” he says, peeling off the coat. “So gross.”

I lean against the wall beside him, and for a long second we just sit there, amid the bones, in the dark. My head is spinning, and my throat is coated with ash, and we both know it’s time to go, but something keeps us there.

“We did it,” says Jacob.

“We did,” I echo, leaning my head against his shoulder.

And then the Catacombs begin to whisper.

Jacob and I exchange a look.

Thomas may be gone, but this place is far from empty.

“Let’s get out of here,” I say, reaching for the Veil.

For an instant, it resists, but then Jacob’s hand joins mine, and together we pass through. A surge of cold hits my lungs, and the world is back, and suddenly bright. A second later, Jacob appears beside me, his usual see-through self, and I look around, worried we’ve wandered too far. But then I hear my parents’ voices, loud and blessedly close, and I round the corner the instant before they turn back and look.