I stepped forward to look inside. What I saw gave me goose-bumps. Like the Siberia Room, it was portal to another time and place. The room’s simple furniture—bed, wardrobe, side table—was caked with sand. The rear wall was missing. Beyond it was a curving palm-fringed beach.

“I give you Rarotonga, 1752!” Bentham declared proudly. “Hello, Sammy! Long time!”

Squatting in the near distance was a small man cleaning a fish. He regarded us with mild surprise, then raised the fish and waved to us with it. “Long time,” he agreed.

“This is good, then?” Emma said to Bentham. “This is what you wanted?”

“What I wanted, what I’ve been dreaming of …” Bentham laughed as he hurried off to throw open another door. Inside was a yawning, tree-filled canyon, a narrow bridge suspended across it. “British Columbia, 1929!” he crowed.

He pirouetted down the hall to open a third door—by now we were chasing him—inside which I could see hulking stone pillars, the dusty ruins of an ancient city.

“Palymra!” he shouted, slapping his hand against the wall. “Huzzah! The damned thing works!”

* * *

Bentham could hardly contain himself. “My beloved Panloopticon,” he cried, throwing his arms wide. “How I missed you!”

“Congratulations,” Sharon said. “I’m glad I could be here to witness this.”

Bentham’s excitement was infectious. It was an astounding thing, his machine: a universe contained in a single hallway. Looking down it, I could see hints of other worlds peeking out—wind moaning behind one door, grains of sand blowing into the hall from beneath another. At any other time, under any other circumstances, I would’ve run and thrown them open. But right now there was only one door I cared about opening.

“Which of these leads inside the wights’ fortress?” I asked.

“Yes, yes, to business,” Bentham said, reining himself in. “My apologies if I got a bit carried away. I’ve put my life into this machine, and it’s good to see it up and running again.”

He leaned against a wall, suddenly sapped of energy. “Getting you into the fortress should be a simple enough proposition. Behind these doors are at least a half dozen crossover points. The question is, what will you do once you get there?”

“That depends,” Emma said. “What are we going to find when we get there?”

“It’s been a long time since I was inside,” Bentham said, “so my knowledge is dated. My brother’s Panloopticon doesn’t look like mine—it is arranged vertically, in a high tower. The prisoners are kept elsewhere. They’ll be in separate cells under heavy guard.”

“The guards will be our biggest problem,” I said.

“I may be able help with them,” said Sharon.

“You’re coming with us?” Emma said.

“Absolutely not!” Sharon said. “But I’d like to do my bit somehow—with minimal risk to myself, of course. I’ll create a disturbance outside the fortress walls that will draw the guards’ attention. That should make it easier for you to skulk about unnoticed.”

“What kind of disturbance?” I asked.

“The wights’ least favorite kind: a civil one. I’ll get those layabouts on Smoking Street to catapult nasty, flaming things at the walls until we’ve got the whole guard force after us.”

“And why would they help you?” Emma said.

“Because there’s lots more where this came from.” He reached into his cloak and pulled out the vial of ambro he’d snatched from Emma. “Promise them enough of it and they’ll do just about anything.”

“Put it away, sir!” Bentham snapped. “You know I don’t allow that in my house.”

Sharon apologized and stuffed the vial back into his cloak.

Bentham consulted his pocket watch. “Now, it’s just after four-thirty in the morning. Sharon, I imagine your disturbers of the peace are asleep. Could you have them riled and ready by six?”

“Absolutely,” Sharon said.

“Then see to it.”

“Happy to be of service.” And with a swoosh of his cloak, Sharon turned and hurried away down the hall.

“That gives you an hour and a half to prepare,” Bentham said—though it wasn’t immediately clear what preparations could be made. “Anything I have is at your disposal.”

“Think,” Emma said. “What would be useful in a raid?”

“Do you have any guns?” I asked.

Bentham shook his head. “PT here is all the protection I need.”

“Explosives?” Emma said.

“I’m afraid not.”

“I don’t suppose you have an Armageddon chicken,” I said, only half kidding.

“A stuffed one, among my displays.”

I imagined throwing a stuffed chicken at a gun-toting wight and wasn’t sure whether to laugh or cry.

“Perhaps I’m confused,” Bentham said. “Why would you need guns and explosives when you can control hollows? There are many inside the fortress. Tame them and the battle is won.”

“It’s not that easy,” I said, weary of explaining. “It takes a long time to take control of even one …”

My grandfather could’ve done it, I wanted to say. Before you broke him.

“Well, that’s your business,” Bentham said, sensing he’d stepped on my toes. “However you accomplish it, the ymbrynes must be your priority. Bring them back first—as many as you can, starting with my sister. They’re the most wanted, the biggest prize, and they’re in the worst danger.”