The room bustled with activity. Librarians of every rank climbed ladders and consulted each other over desks, overseen by a bespectacled archivist. No one would look at her twice if she were wearing an apprentice’s pale blue robes, but she was certain the archivist would notice her if she went up one of the ladders and started going through the tiny gilded drawers that covered every inch of the walls. And there weren’t many places to hide in there, aside from beneath the desks and behind a few display cases containing grimoires.

She eyed the nearest display case. The grimoire inside looked familiar, and indeed, she recognized it from Summershall, where another copy was on display in the hall outside the reading room. It was an ostentatious-looking Class Four called Madame Bouchard’s Harmonic Cantrips, its cover bracketed in gold and stitched with peacock feathers. Elisabeth’s heart raced as a plan began to unfold within her mind. The only problem was that she couldn’t do it alone.

A throaty growl drew her attention to the nearest section of bookcases. A marmalade-colored cat crouched there, fur standing on end, its tail lashing back and forth. Opposite it sat Silas, looking supremely unconcerned. As the other cat continued to yowl, he raised one of his dainty paws and licked it.

“Silas,” Elisabeth hissed. She went over and scooped him up. The other cat bolted. “I need your help,” she whispered, ignoring the strange look sent to her by a passing apprentice.

Silas gazed at her levelly.

“It’s important,” she tried.

His tail flicked, in a fashion that suggested he was feeling inconvenienced. She suspected he still hadn’t gotten over the Sir Fluffington incident.

“If you leave me to my own devices,” she told him, “I’m likely to get into trouble, and I’m certain Nathaniel wouldn’t appreciate that.”

Silas’s yellow eyes narrowed. Slowly, he blinked.

Elisabeth sagged in relief. “Good. Now, here’s what I need you to do. . . .”

None of the librarians in the catalogue room paid any mind when, a few minutes later, a small white cat trotted inside. Not a soul reacted when he leaped onto one of the desks and minced across it. But they did pay attention when Silas launched himself at the glass display case, knocked it askew, and promptly streaked from the scene, looking for all the world like an ordinary cat that had gotten himself into unexpected trouble. Everyone froze as the case wobbled once—twice—then tumbled to the floor and shattered.

Madame Bouchard’s Harmonic Cantrips seemed to have been waiting its entire life for this moment. It rose gloriously from the wreckage, unfurling a set of paper wings, which were a good seven or eight feet across. As the librarians shielded their heads from its flapping pinions, it spread its pages wide and unleashed a shrill, operatic wail. Desks trembled. Drawers rattled. The archivist’s spectacles cracked. Librarians fled in every direction, covering their ears against the ear-splitting vibrato.

Elisabeth waited until the last librarian emptied out before she darted inside. She set her teeth against the noise—seeing that it possessed an audience, Madame Bouchard had launched into an aria—and glanced around at the drawers. The cataloguing system was different here than in Summershall, and there had to be thousands of drawers altogether. However, she swiftly determined that the drawers were divided into seven different columns, with bronze numerals fixed above them ranging from I to VII. Those had to represent grimoire classes, with classes Eight through Ten omitted from the public catalogue.

She had previously estimated that the Codex was either a Class Five or a Class Six. She clambered up the ladder belonging to the Class Five section first, and found the drawer marked “Pe—Pi.” After flipping through the cards and finding nothing, she checked the drawer labeled “Ci—Co,” in case the grimoires were catalogued by title instead of author. When that proved unsuccessful, she moved to the Class Six section with her nerves shrieking nearly as loudly as Madame Bouchard. During the brief intervals in which the grimoire paused for breath, she heard shouts ringing across the atrium, rapidly drawing closer.

She found the Codex’s card in the last drawer she checked, glanced at it, and slammed the drawer shut. As she leaped off the ladder, a warden came striding inside with a salt round at the ready and a length of iron chain. He stared at Elisabeth in bewilderment. She seized her broom and clutched it tightly.

“What are you doing in here?” he shouted over Madame Bouchard, who was now energetically practicing scales.

Elisabeth swept a bit of broken glass aside. “I’m cleaning up the mess, sir!” she shouted back.

A whirlwind of chaos ensued. The warden at last handed her off to an equally baffled librarian, who said, “Well, I must commend you for going above and beyond the call of duty, girl,” and brought her back to Gertrude, who gave her a thorough scolding. But Elisabeth wasn’t in any real trouble, for she could hardly be punished for sweeping a floor.

She spent the rest of the day meekly obeying Gertrude’s commands. Under different circumstances she wouldn’t have been able to wait to race back home and tell Katrien what she had done, as it was exactly the sort of story that her friend would love. But what she had seen on the catalogue card shadowed her mood like a dark cloud. She didn’t want to tell Katrien about it; she didn’t even want to think about it herself.

The Codex Daemonicus wasn’t going to be easy to steal, because it was shelved in the restricted archives of the Northwest Wing.

TWENTY

ELISABETH SLEPT POORLY that night, and had unsettling dreams. In them, she walked down the Northwest Wing’s dark corridor, the gate looming larger and larger above her, stretching impossibly high. As she drew near, the gate creaked open of its own accord. A shape stood within the swirling mist beyond, waiting for her, its presence suffusing her with bone-deep horror. Before she made out who or what it was, she always jolted awake.

She wished she could speak to Katrien again, but the mirror’s magic only renewed itself every twelve hours or so, and they had to save their brief conversations for important matters. They couldn’t lie in bed and talk well into the night as they had in Summershall, bright-eyed and restless in the dark. As a last resort Elisabeth imagined she was back in their drafty tower room, snug beneath the familiar weight of her quilt, safe behind the library’s thick stone walls, until she drifted once more.

It was no use. She had returned to the gate, and the ominous figure still awaited her. This time, when the gate swung open, it opened its mouth and screamed.

Elisabeth’s eyes snapped open, her pulse racing. But the screams didn’t fade. They ground against her skull, echoing ceaselessly from every direction. They hadn’t happened in her dream—they were real.

She leaped from bed and belted on her salt rounds, then seized a poker and stumbled into the hall, where the screams grew louder. They came from the floor, the ceiling. They tore forth from the very walls. It was as though the house itself had begun howling in anguish.

A whiff of aetherial combustion drifted over her, and her stomach clenched with dread. Someone was performing sorcery. What if Ashcroft had spotted her in the Royal Library after all, and had traced her back here—and was now launching an attack on Nathaniel’s house?

Without thinking, she headed for Nathaniel’s room. He would know what to do. The screams throbbed painfully in her ears as she sprinted down the hallway, poker at the ready. She turned a corner and drew up short.