There was a momentary lull in the blasting noises coming from the cavern, and Emma was finally able to hug me. “I saw him shoot you! By what miracle are you alive?”

“By the miracle of peculiar sheep’s wool and Horace’s dreams!” I said, and then I kissed Emma and broke away to find Horace in the crowd. When I did, I hugged him so hard his patent leather shoes lifted off the ground. “I hope one day I’ll be able to repay you for this,” I said, tugging on my scarf.

“I’m so glad it helped!” he said, beaming at me.

The destruction resumed, the sound immense, unbelievable. Rocky debris rolled out of the corridor at us. Even if Caul and Bentham couldn’t reach us from where they were, they could still bring the whole place crashing down on our heads. We had to get out of the library—and then out of this loop.

We ran, scraping and hobbling back the way we’d come, half of us a limping mess, the others acting as human crutches. Addison guided us with his nose, back through the maze and out the way we’d come. The sound of Caul and Bentham’s battle seemed to pursue us, growing louder even as we got farther away, as if they were growing. How big could they get, and how strong? Perhaps the souls from all the jars they’d broken were raining into the pool, feeding them, making them even more monstrous.

Would the Library of Souls bury them? Would it be their grave, their prison? Or would it crack open like an eggshell and birth these horrors into the world?

We reached the grotto exit and dashed once again into the orange daylight. The rumble behind us had become constant, a quake that reverberated through the hills.

“We must keep going!” Miss Peregrine shouted. “To the loop exit!”

We were halfway there, stumbling through a clearing, when the ground beneath us shook so violently that we were all thrown off our feet. I’d never heard a volcano erupt in person, but it couldn’t have sounded much scarier than the thunderous boom that echoed from the low hills behind us. We turned in shock to see acres of pulverized rock flying into the air—and then we heard, clear as day, the screams of Bentham and Caul.

They were free of the library now. They had torn through the cavern ceiling, and untold depths of stone, to daylight.

“We can’t wait any longer!” Miss Peregrine cried. She picked herself up and held aloft Bentham’s crumple of paper. “Sisters, it’s time to close this loop!”

That’s when I realized what it was he’d given us, and why Miss Peregrine had let him go. A recipe, he’d called it. It worked once …

It was the procedure he’d tricked Caul and his followers into enacting, all those years ago in 1908. The one that had collapsed the loop they were in, rather than resetting their internal clocks as they’d hoped. This time the collapse would be intentional. There was only one problem …

“Won’t that turn them into hollows?” asked Miss Wren.

“A hollow’s no problem,” I said, “but last time someone collapsed a loop this way, didn’t it make an explosion big enough to flatten half of Siberia?”

“The ymbrynes my brother coerced into helping him were young and inexperienced,” Miss Peregrine said. “We’ll do a better job.”

“We’d better,” said Miss Wren.

Over the hill, a giant face rose like a second sun peeking over the horizon. It was Caul, large as ten houses now. In a terrible voice that trumpeted across the hills, he bellowed, “ALMAAAAAAAAA!”

“He’s coming for you, miss!” Olive cried. “We must get to safety!”

“In a moment, dear.”

Miss Peregrine shooed all of us peculiar children (and Sharon and his cousins) a good distance away, then gathered the ymbrynes around her. They looked like some mystical secret society about to enact an ancient ritual. Which, I suppose, they were. Reading from the paper, Miss Peregrine said, “According to this, once we start the reaction, we’ll have only a minute to escape the loop.”

“Will that be that enough time?” said Miss Avocet.

“It’ll have to be,” said Miss Wren grimly.

“Perhaps we should get closer to the exit before we try,” suggested Miss Glassbill, who had just recently come to her senses.

“There isn’t time,” said Miss Peregrine. “We have to—”

The rest of her sentence was drowned out by a distant-but-thunderous shout from Caul, his words gibberish now, his mind likely melting from the extraordinary stress of rapid growth. His breath reached us a few seconds after his voice, a foul yellow wind that curdled the air.

Bentham hadn’t been heard from in a few minutes. I wondered if he’d been killed.

“Wish your elders luck!” Miss Peregrine shouted to us.

“Good luck!” we all cried.

“Don’t blow us up!” Enoch added.

Miss Peregrine turned to her sisters. The twelve ymbrynes formed a tight circle and joined hands. Miss Peregrine spoke in Old Peculiar. The others replied in unison, all their voices rising in an eerie, lilting song. This went on for thirty seconds or more, during which time Caul started to climb out of the cavern, rubble tumbling down the hills where his massive hands grasped for purchase.

“Well, this is fascinating,” Sharon said, “and you’re all free to stay and watch, but I think my cousins and I will be going.” He began to walk away, then saw that the path ahead split five ways, and the hard ground had captured none of our footprints. “Um,” he said, turning back, “does anyone happen to remember the way?”