“How delightful. Just show us the way, dear.”

She didn’t have a key that would open the cage, but she didn’t need one. She wedged Demonslayer between its bars and twisted, bending the old, brittle iron until it curved enough for the grimoire to flutter free. Then she snatched up the Illusarium’s glass ball and ran onward. An illusion ghosted to life at her side: the Director, Irena, her molten red hair flowing into the mist. Pride illuminated her wan features as she gave Elisabeth the faintest of smiles. Before Elisabeth could call out to her, she was gone, subsiding back into vapor.

Nathaniel made a choked-off sound. At first she thought he had seen Irena, too. But when she looked at him, his head was turned toward a different spot in the mist, where the figures of a smiling woman and a small, grave boy in a suit were swirling away. Silas gazed in the same direction, his eyes as bright as gemstones. The Illusarium had shown Nathaniel something else—his family. She freed one of her hands and sought his. Their fingers intertwined, squeezing tightly.

Moments later, they burst through the gate. A tidal wave of grimoires swept after them, tumbling into the Northwest Wing at their heels. Leading the expanding swell of parchment and leather, they flew past the skeletal angels carved into the archway and careened around the corner, straight into an army of demons.

Her heart nearly stopped. Scales and horns and wattles filled every inch of the atrium. Rifts spiraled up the tiered bookshelves, rising toward the dome, whose indigo glass had begun to shatter, the suspended shards glinting against the Otherworld’s sky. More fiends leaped from the rifts every second. Imps scampered across the railings, and goblins loped along the balconies on all fours. There were hundreds of demons. Possibly even thousands of them.

But Ashcroft’s forces were still outnumbered.

An imp stopped gnawing on a bookshelf to glance in their direction. Then, slowly, it looked up. Its black eyes widened, reflecting a swarm of specks, each shape growing larger by the second. A shadow stretched across the atrium as the grimoires came crashing down.

Elisabeth braced herself. An instant later, her world dissolved into a maelstrom of pages. She and Nathaniel stood hand in hand, their hair whipped by the wind, Silas digging his claws into Nathaniel’s coat, everything blocked out by a seemingly endless cyclone of parchment that battered them like thousands of wings. The smell of ink and magic and dust choked her nostrils. For a moment, she couldn’t breathe. And then, as abruptly as a flock of birds whirling past, the torrent ceased and their surroundings cleared.

For every demon, there were a dozen grimoires. A goblin keeled over, engulfed by a throng of books that surged over its body like a school of piranhas, gnashing and snapping their teeth. An imp squawked as pages snapped shut on its long ears, lifting it into the air. Nearby, a withered face rose above a pair of fiends, evaluating them like a professional seamstress. A needle whipped expertly between them, and they toppled to the floor, laced together with thread. Across the atrium, demons foundered, howling at paper cuts and blinded by wads of ink.

Rallied to action, grimoires cascaded from the balconies in waterfalls of gilt and multicolored leather. Dust clouds rose as they spilled onto the tiles from three, four, even five stories up. A flash of peacock feathers came from the direction of the catalogue room, and Madame Bouchard’s operatic wail sent fiends writhing and pawing at their ears.

“We need to find Ashcroft!” Elisabeth yelled. Her voice sounded like a mosquito’s whine, barely audible through the din. “He has to be here somewhere!”

Nathaniel caught her shoulder and pointed. Shards of the dome had begun to funnel downward toward the center of the atrium, siphoned by some unseen force. They exchanged a glance, then looked back to the chaos in front of them. The grimoires were winning—but they needed to be winning faster.

Struck by inspiration, Elisabeth set the Illusarium on the floor and brought Demonslayer’s hilt down on its orb, splintering the glass. Mist gushed from the cracks, enveloping her in a damp, clinging grayness. When the vapor finished pouring out, the container rolled over, empty. She stared at it in shock. Had there been anything inside?

“Ahhhhhhh,” a ghostly voice breathed, emanating from nowhere and everywhere at once. Mist boiled across the atrium, reducing the combatants to shadows in the fog. Fiends lunged toward figures that rose from the mist, only to slump back down and tauntingly reappear behind them. Taking advantage of their distraction, the grimoires set upon them in earnest. Elisabeth watched a goblin attempt to dive out of the mist, then get dragged back in by an unseen force, leaving a silent ripple in the vapors. Yelps and whimpers followed. Then the sounds cut off abruptly, and an eerie stillness fell.

She and Nathaniel dashed forward as the mist began to shred away, catching on the prone, scattered bodies of demons. She could barely believe it. None had been left standing.

“Look,” Nathaniel said. “What are they doing?”

Pages whispered. One by one, grimoires were lifting from the mist. They came together in groups and rose upward toward the balconies in spiraling streams, like flocks of birds taking flight in slow motion. Elisabeth’s eyes widened when she saw where they were headed. Each stream was flowing toward a rift.

Her first stunned thought was that the rifts were drawing them in, attempting to destroy them. But the grimoires weren’t struggling. They were ascending peacefully, purposefully. Every time a book touched the surface of a rift, it flashed and disintegrated to ashes—and the rift’s edges shrank inward ever so slightly, like wounds beginning to heal. Singing echoed throughout the fractured dome: high, clear notes, as pure and silver as starlight.

“They’re trying to close the rifts.” Elisabeth’s heart squeezed like a fist. “They’re sacrificing themselves to save the library.”

There went Madame Bouchard. And there, falling in a rain of ash, the Class Four who had spat ink at the apprentices every morning. Each of those books possessed a soul. Many were centuries old, irreplaceable. And some of them had just now tasted freedom for the first time since they had been created—only minutes of it, after a lifetime of imprisonment. Still they sang as they gave their lives.

Tears stung Elisabeth’s eyes. She couldn’t let their sacrifice be in vain.

The mist was almost gone now; the pall was brightening. As the last few wisps swirled away, she and Nathaniel stumbled into the middle of the atrium, into Ashcroft’s summoning.

A figure stood ahead, shards of glass circling it like planets orbiting a sun. It was taller than a man, slender and luminous, but even when Elisabeth squinted directly at it, she couldn’t make out its features. She had the strange thought that it was like sunlight reflected by a mirror: shifting and intangible, a mere specter of something far greater, radiant and terrible to behold.

Head bent, it regarded the human standing at its feet.

Ashcroft.

He gazed up at the Archon, entranced, bathed in its glow, seemingly oblivious to the battle that had raged around him. Its radiance transformed his features. He looked a decade younger, his expression one of almost innocent yearning. Blood twined down his left wrist, clasped beneath his other hand. A dagger lay forgotten nearby.

Hope leaped within Elisabeth. He hadn’t finished the ritual. The Archon was still inside its circle—a circle formed by the map of the library patterned on the floor in tile, which she had walked over dozens of times, never suspecting its purpose.