The bell tower was shingled with chalky shades of blue, red, and brown, striped like snakeskin. Spotlights went up the sides of the tower and ended in the clouds. I felt an unbearable sense of need rattle me, and I fell to my knees and looked up. When I saw the cross, for the first time in my life it meant something new-no longer did I see a symbol of membership, of fraternity or conversion. Now it was something internal: the intersection of my spine and shoulders. It was a cross inside me, a steel frame, holding me up against the unstoppable urge to crumble. I wanted a religious experience. I wanted a voice and I was instead consumed by an almost infinite silence. The harder I begged that building to speak, the more quiet, the more alone I felt, kneeling in an empty lawn and looking up at a silent building. And yet, in that moment, I had the truest religious experience I believe there is: for I was suddenly filled with the desire to be good, even if no one was watching.

I did one last thing. I wrote a letter to my dad and put it in the mail. It’s hard to even call it a letter-it was just one line. It said:

You are not small to me.

I retraced my steps from Bernini’s office to the steam tunnel door with eyes above it. I passed through the three rooms. The doors were all open now. The mechanisms were silent. It felt like an abandoned movie set. Or, even better, it felt like something I remembered from my childhood, an amazing, unexplainable feeling that was new to my generation, since we were the first generation to grow up with computers. It felt like a computer game, after you’d solved all the puzzles and done everything you were supposed to do for that level. All that was left was to move on. But if you postponed that-if you walked around that world just a little bit longer-it took on an uncanny feeling. The characters were still there, little animated men running through their programmed routines, tending bar, sweeping porches, working the docks of the pirate shipyard. But it no longer felt like a real world, because your tasks were done and the characters had nothing left to say to you, and you saw through the illusion of their activity.

I found myself past the last room and standing above the hole where the trapdoor still hung open. I let my feet stick out over the edge.

I took a deep breath, and I jumped.

37

I fell, and the walls of the hole arced and I went into a slide that sent me hurtling. Miles’s satchel was across my waist; I had one hand over it and one protecting my head. I was rolling over myself now, smacking different parts on the packed dirt of the walls. And yet there was something thrilling about it. I felt free. I felt hope. I was going to rescue Sarah. This was an adventure, and nothing was going to stop me!

The walls leveled out as I fell until they became ground below me and a ceiling above, depositing me in a wild roll until I skidded in a mounting pile of dirt. I plowed to a stop. My eyes were closed. I froze for a moment and listened. Nothing. No explosions, no snarls, no voices, not even crickets chirping. Just the light sound of air moving through cracks.

Did my fingers and toes still move? Check. Vision intact? Check. Wooden spikes through my torso? Negative.

Things were looking up.

It smelled pungent down here, thick and muddy. The rocky walls were covered with writing, more mathematical than pictorial. They still looked primitive. Maybe this was once the home of the Einstein of cavemen.

My body was sore, but I was okay.

I saw a hallway chiseled through the rock. I moved too quickly and was almost seen by three people at the end of the hall, but they were absorbed in conversation and I pressed myself against the wall faster than I realized I could move.

At the distant end of the hall were three women. Their lips were moving, but I couldn’t hear them speak. They were young. They reminded me of pretty mothers at a playground. Their skin was almost luminous, lit by a shaft of pale light from slats above them. They seemed lighthearted. One of them laughed. The women moved away together, so gracefully that it wasn’t at all clear they were walking. They disappeared around a corner.

I went down the hall after them. I stepped slowly and hoped no one would come around the bend ahead and see me. But it was completely silent. Every step I took, gravel crackled under my shoes. I clutched Miles’s bag and felt the metal inside. It was comforting.

I got to the spot where the women had turned and was hit with a blast of cool, fresh air. The dirt path I’d followed forked and continued also in the other direction, around another turn. For a moment, I started to follow the women, but something told me not to. I turned and went left instead of right. I can’t tell you why. But I was glad I did. Because the path brought me to a stone stairway within a tight, ascending passage lined with columns on either side. The steps were wide but the stairway was steep, the end high above me. As I neared the top, I saw I was heading toward a slanted opening, like the entrances of Assyrian temples I’d seen in history books. No sound, no movement from that opening as I climbed. But when I reached the top, I looked through the door and saw a room I’d seen before. An altar in the center. A pole that loomed from the floor to the high stone ceiling. And beyond all that, a machine, quietly thrumming and moving in the shadows.

38

The machine reminded me of a spider, the way its long spindles bent in unnatural places, producing movements that were alive but definitely not human. Not even mammalian, for that matter. It creeped me out. It was machinelike in an ancient way, like the Gutenberg press. It could have been hundreds of years old. How long had these people been replicating themselves? How many centuries had they lived?

The machine was also larger than I ever imagined, seeing it through the slots of that vent, looking down. The thin spindle arms spread out from the central mechanism; they filled the room and towered over me. The arms bent and gyrated at joints, like bones. They traced out the points in space of the ritual dance without really capturing what was alive about the dancers-the way stars could be connected into bears and scorpions without blood or brains.

I wanted to get out of here as quickly as possible. I wanted to rescue Sarah (if she’s still alive, the wicked voice in my head whispered) and leave this place. But I knew what I had to do first. If my theory was right, this machine was the artificial heart that kept the possessed imprisoned. Smashing it to pieces, prying it apart-that would make noise. That would give me away. But if I could do it fast enough, I could free Nigel, Daphne, John, and everyone else. And the people coming to capture me would no longer have bodies to grab me with. That was the theory, anyway.

You know the old joke about the economist stranded on an island. He decides to build a shelter and says: First, assume a hammer.

If I was wrong, I wouldn’t have a chance to find Sarah.

But if I went looking for Sarah, somewhere in this huge place, I might never get back here and have this chance again.

The tie-breaker was simple: I knew what Sarah would want me to do.

I reached into Miles’s satchel and pulled out the crowbar. I moved into the room and walked the steps up to the altar and the machine behind it.

And that’s when I saw something that made my heart stop and took the air out of my lungs.

There was a person chained to the slab on the altar. His voice was muffled with a gag. His wrists were raw and purple from the shackles. When he saw me, he started struggling violently against the chains and looked at me with wide, pleading eyes.