“But that’s not what happened,” said Emma.

“Is that when half of Siberia got blown up?” I asked.

“The reaction was so strong, it lasted a day and a night,” said Bentham. “There are photos of it, and of the aftermath …”

He nodded at the album on the floor, then waited while we found the pictures. One, taken at night in some indistinct wilderness, was striped by a jet of vertical flame, a massive but distant release of white-hot energy that lit the night like a skyscraper-sized Roman candle. The other was a ruined village made up of rubble and cracked houses and trees raked clean of bark. Just looking at it, I could almost hear a lonely wind blowing; the palpable silence of a place robbed suddenly of life.

Bentham shook his head. “Never in my wildest dreams did I imagine what would crawl out of that collapsed loop,” he said. “For a brief time afterward, things were quiet. Released from confinement, I began to recover. I regained control of my machine. It seemed my brother’s dark age had drawn to a close—but it was only beginning.”

“That was the start of the Hollow Wars,” Emma said.

“Soon we began to hear stories about creatures made of shadow. They were emerging from the ruined forests to feed on peculiars—and normals, and animals, and anything that would fit between their jaws.”

“Once I saw one eat a car,” Nim said.

I said, “A car?”

“I was inside it,” he replied.

We waited for him to elaborate.

“And?” said Emma.

“I got away,” he said, shrugging. “The steering column got stuck in its throat.”

“May I continue?” said Bentham.

“Of course, sir. My apologies.”

“As I was saying, there wasn’t much that would stop these new abominations, save the odd steering column—and loop entrances. Luckily, we had plenty of those. So most of us dealt with the hollowgast problem by staying put in our loops, venturing out only when we had no choice. The hollows didn’t end our lives, but they made them vastly more difficult, isolated, and dangerous.”

“What about the wights?” I asked.

“I imagine he’s coming to that,” said Emma.

“I am,” said Bentham. “Five years after encountering my first hollowgast, I met my first wight. There was a knock at my door after midnight. I was in my house, safe inside my loop—or so I thought. But when I opened the door, there stood my brother Jack, a bit worse for wear but looking like his old self—save his dead eyes, which were blank as unmarked paper.”

Emma and I had folded ourselves into cross-legged positions and were now leaning toward Bentham, hanging on his every word. Bentham stared over our heads with haunted eyes.

“He’d consumed enough peculiars to fill his hollow soul and turn himself into something that resembled my brother—but wasn’t, quite. What little humanity he’d clung to through the years was gone completely, leaked away with the color in his eyes. A wight is to the peculiar he once was as a thing copied many times is to its original. Detail is lost, and color …”

“What about memory?” I asked.

“Jack retained his. A pity: otherwise he might’ve forgotten all about Abaton and the Library of Souls. And what I’d done to him.”

“How did he find out it was you?” Emma asked.

“Chalk it up to brotherly intuition. And then one day, when he had nothing better to do, he tortured me until I confessed to it.” Bentham nodded at his legs. “Never quite healed properly, as you can see.”

“But he didn’t kill you,” I said.

“Wights are pragmatic creatures, and revenge is not a great motivator,” Bentham said. “Jack was more obsessed than ever with finding Abaton, but to do it he needed my machine—and me to operate it. I became his prisoner and his slave, and Devil’s Acre the secret headquarters for a small but influential contingent of wights bent on finding and cracking open the Library of Souls. Which is, you’ll have guessed by now, their ultimate goal.”

“I thought they wanted to re-create the reaction that turned them into hollows,” I said, “only bigger and better. ‘Do it right this time,’ ” I said, making air quotes.

Bentham frowned. “Where did you hear that?”

“A wight told us just before he died,” Emma said. “He said that’s why they needed all the ymbrynes. To make the reaction more powerful.”

“Utter nonsense,” Bentham said. “Probably just a cover story to throw you off the scent. Though it’s possible the wight who told you this lie believed it. Only Jack’s innermost circle knew about the search for Abaton.”

“But if they didn’t need the ymbrynes for their reaction,” I said, “then why’d they go to all the trouble of kidnapping them?”

“Because the lost loop of Abaton isn’t just lost,” said Bentham. “According to legend, before it was lost it was also locked—and it was ymbrynes who locked it. Twelve of them, to be exact, who came together from twelve far-flung corners of peculiardom. To open Abaton again, if you can manage to find it, would require those same twelve ymbrynes, or their successors. So it’s no surprise that my brother has kidnapped precisely twelve ymbrynes, whom he spent many years hunting and tracking.”

“I knew it,” I said. “It had to be something more than just re-creating the reaction that turned them into hollows.”