“There are a few tricks to learning your way around the Institute that I ought to teach you,” he said, still not looking at her. There was something oddly diffident in his attitude now that hadn’t been there moments before, as if Tessa had done something to offend him. But what could she have done? “Ways to identify the different doors and turn—”

He broke off, and Tessa saw that someone was coming down the corridor toward them. It was Sophie, a basket of laundry tucked under one of her arms. Seeing Will and Tessa, she paused, her expression growing more guarded.

“Sophie!” Will’s diffidence turned to mischief. “Have you finished putting my room in order yet?”

“It’s done.” Sophie didn’t return his smile. “It was filthy. I hope that in future you can refrain from tracking bits of dead demon through the house.”

Tessa’s mouth fell open. How could Sophie talk to Will like that? She was a servant, and he—even if he was younger than she was—was a gentleman.

And yet Will seemed to take it in stride. “All part of the job, young Sophie.”

“Mr. Branwell and Mr. Carstairs seem to have no problem cleaning their boots,” Sophie said, looking darkly from Will to Tessa. “Perhaps you could learn from their example.”

“Perhaps,” said Will. “But I doubt it.”

Sophie scowled, and started off along the corridor again, her shoulders tightly set with indignation.

Tessa looked at Will in amazement. “What was that?”

Will shrugged lazily. “Sophie enjoys pretending she doesn’t like me.”

“Doesn’t like you? She hates you!” Under other circumstances, she might have asked if Will and Sophie had had a falling out, but one didn’t fall out with servants. If they were unsatisfactory, one ceased to employ them. “Did—did something happen between you?”

“Tessa,” Will said with exaggerated patience. “Enough. There are things you can’t hope to understand.”

If there was one thing Tessa hated, it was being told that there were things she couldn’t understand. Because she was young, because she was a girl—for any of a thousand reasons that never seemed to make any real sense. She set her chin stubbornly. “Well, not if you won’t tell me. But then I’d have to say that it looks a great deal like she hates you because you did something awful to her.”

Will’s expression darkened. “You can think what you like. It’s not as if you know anything about me.”

“I know you don’t like giving straightforward answers to questions. I know you’re probably around seventeen. I know you like Tennyson—you quoted him at the Dark House, and again just now. I know you’re an orphan, as I am—”

“I never said I was an orphan.” Will spoke with unexpected savagery. “And I loathe poetry. So, as it happens, you really don’t know anything about me at all, do you?”

And with that, he spun on his heel and walked away.

5

THE SHADOWHUNTER’S CODEX

Dreams are true while they last, and do we not live in dreams?

—Alfred, Lord Tennyson, “The Higher Pantheism”

It took an age of wandering glumly from corridor to identical corridor before Tessa, by lucky chance, recognized a rip in yet another of the endless tapestries and realized that the door to her bedroom must be one of the ones lining that particular hallway. A few minutes of trial and error later, and she was gratefully shutting the correct door behind her and sliding the bolt home in the lock.

The moment she was back in her nightgown and had slipped under the covers, she opened The Shadowhunter’s Codex and began to read. You’ll never understand us from reading a book, Will had said, but that wasn’t the point really. He didn’t know what books meant to her, that books were symbols of truth and meaning, that this one acknowledged that she existed and that there were others like her in the world. Holding it in her hands made Tessa feel that everything that had happened to her in the past six weeks was real—more real even than living through it had been.

Tessa learned from the Codex that all Shadowhunters descended from an archangel named Raziel, who had given the first of them a volume called the Gray Book, filled with “the language of Heaven”—the black runic Marks that covered the skin of trained Shadowhunters such as Charlotte and Will. The Marks were cut into their skin with a styluslike tool called a stele—the odd penlike object she’d seen Will use to draw on the door at the Dark House. The Marks provided Nephilim with all sorts of protection: healing, superhuman strength and speed, night vision, and even allowed them to hide themselves from mundane eyes with runes called glamours. But they were not a gift anyone could use. Cutting Marks into the skin of a Downworlder or human—or even a Shadowhunter who was too young or improperly trained—would be torturously painful and result in madness or death.

The Marks were not the only way they protected themselves—they wore tough, enchanted leather garments called gear when they went into battle. There were sketches of men in the gear of different countries. To Tessa’s surprise, there were also sketches of women in long shirts and trousers—not bloomers, such as the sort she’d seen ridiculed in newspapers, but real men’s trousers. Turning the page, she shook her head, wondering if Charlotte and Jessamine really wore such outlandish getups.

The next pages were devoted to the other gifts Raziel had given the first Shadowhunters—powerful magical objects called the Mortal Instruments—and a home country: a tiny piece of land sliced out of what was then the Holy Roman Empire, surrounded with wardings so that mundanes could not enter it. It was called Idris.

The lamp flickered low as Tessa read, her eyelids slipping lower and lower. Downworlders, she read, were supernatural creatures such as faeries, werewolves, vampires, and warlocks. In the case of vampires and werewolves, they were humans infected with demon disease. Faeries, on the other hand, were half-demon and half-angel, and therefore possessed both great beauty and an evil nature. But warlocks—warlocks were the direct offspring of humans and demons. No wonder Charlotte had asked if both her parents were human. But they were, she thought, so I can’t possibly be a warlock, thank God. She stared down at an illustration showing a tall man with shaggy hair, standing in the center of a pentagram chalked onto a stone floor. He looked completely normal, save for the fact that he had eyes with slit pupils like a cat’s. Candles burned at each of the star’s five points. The flames seemed to slide together, blurring as Tessa’s own vision blurred in exhaustion. She closed her eyes—and was instantly dreaming.

In the dream she danced through whirling smoke down a corridor lined with mirrors, and each mirror she passed showed her a different face. She could hear lovely, haunting music. It seemed to come from some distance away, and yet was all around. There was a man walking ahead of her—a boy, really, slender and beardless—but though she felt that she knew him, she could neither see his face nor recognize him. He might have been her brother, or Will, or someone else entirely. She followed, calling to him, but he receded down the corridor as if the smoke carried him with it. The music rose and rose to a crescendo—

And Tessa woke, breathing hard, the book sliding off her lap as she sat up. The dream was gone, but the music remained, high and haunting and sweet. She made her way to the door and peered out into the hallway.

The music was louder in the corridor. In fact, it was coming from the room across the hall. The door was ajar slightly, and notes seemed to pour through the opening like water through the narrow neck of a vase.

A dressing gown hung on a hook by the door; Tessa drew it down and slipped it on over her nightclothes, stepping out into the hallway. As if in a dream, she crossed the corridor and put her hand gently to the door; it swung open under her touch. The room within was dark, lit only by moonlight. She saw that it was not unlike her own bedroom across the hall, the same large four-poster bed, the same dark heavy furniture. The curtains had been pulled back from one tall window, and pale silver light poured into the room like a rain of needles. In the square patch of moonlight before the window, someone was standing. A boy—he seemed too slight to be a grown man—with a violin propped against his shoulder. His cheek rested against the instrument, and the bow sawed back and forth over the strings, wringing notes out of it, notes as fine and perfect as anything Tessa had ever heard.

His eyes were closed. “Will?” he said, without opening his eyes or ceasing to play. “Will, is that you?”

Tessa said nothing. She could not bear to speak, to interrupt the music—but in a moment the boy broke it off himself, lowering his bow and opening his eyes with a frown.

“Will—,” he started, and then, seeing Tessa, his lips parted in surprise. “You’re not Will.” He sounded curious, but not at all annoyed, despite the fact that Tessa had barged into his bedroom in the middle of the night and surprised him playing the violin in his nightclothes, or what Tessa assumed were his nightclothes. He wore a light loose-fitting set of trousers and a collarless shirt, with a black silk dressing gown tied loosely over them. She had been right. He was young, probably the same age as Will, and the impression of youth was heightened by his slightness. He was tall but very slender, and disappearing below the collar of his shirt, she could see the curling edges of the black designs that she had earlier seen on Will’s skin, and on Charlotte’s.

She knew what they were called now. Marks. And she knew what they made him. Nephilim. The descendant of men and angels. No wonder that in the moonlight his pale skin seemed to shine like Will’s witchlight. His hair was pale silver as well, as were his angular eyes.

“I’m so sorry,” she said, clearing her throat. The noise sounded terribly harsh to her, and loud in the silence of the room; she wanted to cringe. “I—I didn’t mean to come in here like this. It’s— My room is across the hall, and …”

“That’s all right.” He lowered the violin from his shoulder. “You’re Miss Gray, aren’t you? The shape-changer girl. Will told me a bit about you.”

“Oh,” Tessa said.

“Oh?” The boy’s eyebrows rose. “You don’t sound terribly pleased that I know who you are.”

“It’s that I think Will is angry with me,” Tessa explained. “So whatever he told you—”

He laughed. “Will is angry with everyone,” he said. “I don’t let it color my judgment.”

Moonlight spilled off the polished surface of the boy’s violin as he turned to lay it down on top of the wardrobe, the bow beside it. When he turned back to her, he was smiling. “I should have introduced myself earlier,” he said. “I’m James Carstairs. Please call me Jem—everyone does.”

“Oh, you’re Jem. You weren’t at dinner,” Tessa recalled. “Charlotte said you were ill. Are you feeling better?”

He shrugged. “I was tired, that’s all.”