The knocking lasted four hours.
It was not loud, and that was the worst part. It was patient. Three slow raps, a pause, three more, like a visitor who had all the time in the world and was a little insulted that no one had answered. It came up through the stone, through the floorboards, through the iron legs of the bed, until Mara could feel it in her back teeth.
Dellie sat cross-legged on her bed in the dark, hugging a pillow shaped like a duck, and did not speak for the first hour. In the second hour she began to hiccup. In the third she offered Mara shortbread again, with great formality, and Mara took it, because the alternative was admitting that her hands were shaking.
"It's only the tide," Dellie said eventually, in the voice of someone reading from a pamphlet.
"The tide doesn't knock."
"It might. Lately. Possibly." The duck was losing the fight. "The school is built on top of a village, you know. Saltwick. It drowned in some storm, ages ago. Most nights it just sighs. Sometimes it hums. Matron says it's the pipes."
"Is it the pipes?"
"Matron also says Cecil is fine."
Mara pulled her knees up to her chest. Through the little window the sea lay black and flat, with a single silver path laid across it by the moon, like a road leading somewhere she did not want to go.
"Dellie. When you said I don't have one. A death. Does that mean I can't..."
"I don't know." It came out very small. "I've never not known before. It's like reaching for a stair that isn't there." Dellie wiped her nose on the duck. "I'm sorry. I'm usually much better company. I'm usually delightful."
"You're fine," said Mara, and found, to her surprise, that she meant it.
Around four in the morning, the knocking stopped. It didn't fade. It stopped mid-rap, like a hand lifted from a door, and the silence afterward was so total that both girls flinched. They looked at each other. Neither said a word. Eventually they slept in their clothes with the lamp still burning, like children after a thunderstorm.
Breakfast at Ravenmoor was served in a hall the size of a train station, under a ceiling so high that small clouds seemed to have formed in it. Long tables ran in rows. Candles floated, or at least hung from nothing, in a way Mara decided not to think about. And at every place setting, before the porridge, before the toast, before anything resembling food, sat a small dish of trifle.
"Rule five," Dellie whispered. "Eat it. All of it. Smile."
Mara looked at the trifle. The trifle looked back at her. It was seven in the morning.
She ate it. It tasted of sherry and raspberries and, faintly, of rain. All around her, a hundred students did the same, slowly, with the grim determination of soldiers.
And they were watching her.
Not openly. Nobody at Ravenmoor seemed to do anything openly. But Mara had spent ten years being stared at by people who couldn't see what she saw, and she knew the signs. Heads turned a fraction too late. Spoons paused halfway to mouths. At the nearest table, two identical red-haired boys stopped mid-sentence, one finishing the other's word, and both glanced at her in the same instant. A tall girl with silver rings on every finger was frowning at a salt cellar that, as Mara watched, rotated slowly to face her. A boy at the end of the row had a shadow that arrived about two seconds after he did.
"They're all descendants," Dellie murmured. "Old bloodlines. The Ashworths, the Fenwick twins, the Calloways. Everyone's got a family curse. You're the only one who showed up without one."
"I have a family. We just don't have a curse. We have a Vauxhall."
"Oh, that's worse. They'll hate that."
"Why?"
"Because it means they don't know where to put you."
That was when Mara noticed him.
He was sitting alone at the far end of the hall, beneath a tall arched window, one boot propped against the table leg. Dark hair, still damp, as though he'd just come in from the rain. A black jacket worn thin at the cuffs. An iron ring on one finger. He wasn't eating his trifle. He was turning the spoon over in his hand, slowly, and looking straight at her with the patient attention of someone who has already decided what he thinks of you and is waiting for you to prove him wrong.
He did not look away when she caught him. He lifted one eyebrow, barely, and returned to his spoon.
"Who is that?"
Dellie followed her gaze and made a small, strangled noise. "Oh no. No, no. Silas Thorne. Do not engage. He's the coven heir. The Thornes have been at Ravenmoor for nine generations and have never once smiled at a first-year."
"He's not smiling."
"He's not smiling at you in a way I find deeply concerning."
The first lesson was Spectral Studies, in a classroom beneath the east stairs, taught by a thin, tired woman named Professor Quill who wore three pairs of glasses on a chain and appeared to have given up on all of them.
"Ghosts are permitted to attend," she announced, "but may not contribute. Mr. Albright, put your hand down. You are dead. You may not raise it."
In the back row, a transparent boy in a ruffled collar lowered his hand with a look of deep injustice.
The only empty seat was at the back, beside the window. Beside Silas Thorne.
Mara sat. Silas did not look up from his notebook. His handwriting was small and exact, and he wrote left-handed, with the iron ring clicking faintly against the page.
"You're staring," he said.
"You're in my seat."
"Your seat is the one nobody wanted." He turned a page. "Nobody wanted you either, as it happens. It's quite a theme."
"Is that supposed to scare me? I've been insulted by a ghost with strong views on plum jam."
That earned her a look. Brief. Gray eyes, tired around the edges. Not friendly, not hostile. Measuring.
"Voss," he said. "There's no coven called Voss."
"I know. I've checked. Twice."
"Then what are you?"
"Late, usually."
Something moved at the corner of his mouth. He suppressed it so quickly she might have imagined it.
Professor Quill clapped her hands. "Today, a little exercise. The salt line. Mr. Thorne, if you would."
Silas rose without a word, took a pouch from his jacket, and walked to the classroom door. There, with the unhurried care of someone who had done it a thousand times, he poured a thin white line across the threshold, edge to edge, not a grain out of place.
"Salt," said Professor Quill, "is a boundary. The dead cannot cross it. The living can, without difficulty. It is a very simple test of which side of the line a person belongs to. Mr. Albright, would you demonstrate?"
The ghost boy drifted to the door, reached out, and was stopped as if by glass. He sighed and floated back. "Told you," he said, which was not permitted, and Professor Quill let it pass.
"Now. The living. One at a time."
The students filed past. Each stepped over the line. Nothing happened. Mara watched them go and felt, absurdly, her pulse climbing, and could not have said why.
"Miss Voss."
She stood. Her chair scraped. In the quiet, it sounded like a scream.
She walked to the door. Silas stood nearby with his arms folded, watching her, not unkindly. The salt shone white against the dark wood. It was only salt. It was a line on a floor. She had stepped over a thousand lines on a thousand floors.
She lifted her foot.
And the salt turned black.
It didn't smoke, or hiss. It simply darkened, grain by grain, from the center outward, as if something were soaking up through the wood. A thin, damp stain spread across the doorway, and the air filled with the smell of low tide.
Somewhere behind her, someone drew a sharp breath.
Mara stood frozen with her foot hovering an inch above the wet black line, and through the floor, through the stone and the cold and the dark beneath the school, she heard it.
A whisper. Not one voice. Hundreds. All speaking together, in the same slow, patient rhythm as the knocking.
Mara.
Mara.
Mara.
She couldn't move. The classroom had gone muffled and far away, as if she were underwater again, and the voices rose around her, tender and terrible, like a crowd of strangers welcoming someone home.
There you are, they said. There you are, there you are.
A hand closed around her wrist.
Silas had crossed the room. He was very pale, and he wasn't looking at the salt. He was looking at her, and there was no suspicion left in his face. There was something much worse.
"Don't answer it," he said, barely audible.
"You can hear them."
His grip tightened. For a moment she thought he might say something more. Then Professor Quill said sharply, "Mr. Thorne, kindly release Miss Voss," and he did, and stepped back, and the black stain on the doorway began, very slowly, to dry.
The whispering stopped. It did not fade. It stopped, like a door being closed.
Mara looked down at her wrist. Five pale marks lay across the skin where his fingers had been, and beneath them, in the shape of a ring, a single line of cold.
When she looked up, Silas was back at his desk, writing in his notebook, left-handed, as though nothing had happened. But the iron ring on his finger, she noticed, had gone dark.
And across the top of the page, in handwriting that shook, he had written a single word and underlined it twice.
Voss