The clock on Aveline's vanity read half past eleven when she gave up on sleep.

She had tried. She had gone to bed at a reasonable hour, with the notebook closed and the betrothal Accord returned to its document case and Lord Severin's letter folded in her drawer. She had lain in the dark and been methodical about it — breath in, breath out, the standard sequence of deliberate relaxation that she had learned years ago from a physician who noted that she showed signs of carrying tension she did not acknowledge. It had not worked. Her mind was doing what it did when it had caught the edge of something that did not add up: running the same circuit over and over, not anxiously but relentlessly, the way a machine keeps running a diagnostic after it has logged an anomaly.

She got up.

The house was quiet at this hour. She moved through the dark hallways by the familiar map of them, not bothering with a lamp, back to her room and the desk and the document case she had told herself she was done with for the evening.

She sat. She opened the case. She lifted out the Accord.

She held it for a moment before opening it, feeling its weight — which was more significant than the physical weight, which was not much. A document. Forty-something pages of formal language and precise legal architecture and, on page thirteen, two layers of text that she was becoming increasingly certain were not a printing artifact.

She set it on the desk and opened to page thirteen.

The memory-projector lamp was still out from the previous evening. She adjusted it to its narrowest aperture and held it over the page at the angle she had found — the precise deviation from vertical that made the second layer faintly visible.

Nothing.

She adjusted by two degrees. Nothing. Three degrees. Four. She was doing this methodically, working through the range of angles with the patience that came from years of detailed technical work, when the lamp heated in her hand and she shifted her grip slightly and the page changed.

There — and then not — and then there again as she held the angle.

A second layer of text, faint as a shadow, living beneath the words she could read. This time she held the lamp steadier, and her eyes adjusted, and the shapes of letters became faintly legible in the way that half-seen things were legible: not sharp, not certain, but present. She could make out portions of words. Not enough to read, but enough to confirm: there was a text here. A complete text, not fragments. Paragraph structure. And in the corner of the page, almost as though added as a final thought, a symbol she recognized from the margins of her mother's engineering notebooks.

She had not thought about that symbol in years. It was a notation Marcelline had used for certain kinds of resonance relationships — dual-state conditions, she had called them. Situations where a system existed in two simultaneous states that would normally be mutually exclusive.

Aveline sat back. Her hand had gone very still.

She was staring at the document and thinking about dual-state conditions and the word Nocturne and the violet sky she had seen in the corner of a reflection when something moved in her peripheral vision.

She looked up.

The mirror on the far wall of her bedroom was large — an old oval mirror in a dark wood frame that had been in this room since before she was born, which meant it had been here when her mother lived in this house. She had looked at it this morning. She had looked at it every morning for twenty-two years. It reflected the window, the corner of her wardrobe, the edge of the desk where she sat. It reflected, now, Aveline herself: dark-clothed, projector lamp in hand, the Accord spread before her.

It reflected all of this exactly as it should.

Except that the person standing behind her reflection was not her.

He had her reflection's proportions — a person's height, a person's shape. But he was facing toward her from the mirror's space rather than away from her into the room, which was wrong, and he had dark hair where the room behind her was pale wall, and he was, with absolute certainty, a man she did not know.

Aveline did not scream. She was later, privately, slightly proud of this. She went very still — the deep stillness of extreme alertness rather than calm — and looked at the mirror, and the man in the mirror looked back at her.

He had Julian's face.

That was the first thing she was certain of and the second thing that confused her, because Julian's face was a face she had studied with some care over the past two days and this was unmistakably the same structure — the same jaw, the same dark hair — but the resemblance was the way a translation resembled its original: accurate in the components, but something had shifted in the rendering. The eyes were different. Julian's eyes were clear and warm and looked at things with the attentiveness of someone genuinely interested. This man's eyes looked at things with the attention of someone who had been paying attention for a very long time and had found most things insufficient, and who was not certain yet whether she was going to be an exception.

He was not in her room. He was in the mirror. He was standing in a space the mirror was showing her that was not the space behind her, because she could see the space behind her clearly in the rest of the mirror's surface, and it contained no one.

"Who are you?" she said.

Her voice was level. She was aware that this was a remarkable thing, given the circumstances, and decided to be grateful for it rather than analyze it.

The man in the mirror looked at her with those tired, assessing eyes and said, in a voice that carried through the glass with the slightly different quality of a voice speaking from a large room:

"My name is Caelan Veyr."

She processed this. "Veyr."

"Yes."

"Julian Veyr's family."

"A different branch," he said. "A different city. A different sky." He paused, choosing each word with the care of someone who did not have much time and did not want to waste any of it. "You are Aveline Corvayne. You are three weeks from signing a document that has two layers of text, of which you have only been given permission to read one. I need you to not sign it until you understand what the second layer says."

Aveline looked at this man who was standing in an impossible space inside her mirror and telling her things about the document on her desk that she had told no one.

"How do you know about the document?" she said.

"Because the same document exists in my city. With my signature on the second layer, and yours."

She looked at the document. She looked at him. Her hands were not shaking, which she noted.

"The second layer of ink," she said slowly. "It's not a printing artifact."

"No."

"It's a second text. A complete second text."

"Yes."

"Saying what?"

Something moved across his face — not evasion exactly, but the expression of a person who knows the answer to a question is going to change the person asking it, and who is giving them a final moment of not-yet-knowing before it does. "Saying what this agreement actually is," he said. "Not what they've told you it is."

The mirror shimmered. Just slightly — a quality shift in the reflective surface, like heat shimmer above summer pavement, like the moment when ice on a window begins to blur at the edges.

"I don't have much time," he said. "This kind of contact is limited. But I need you to know one thing before the glass closes."

She waited.

"The woman who warned you about two skies," he said. "Your mother — she didn't die. She's been trying to reach you."

The mirror went still. The shimmer stopped. He was gone.

Aveline sat in front of the ordinary reflection of her ordinary room and looked at the wall where a man had just been standing inside a glass, telling her impossible things about her mother.

Her hands, she noticed, were shaking now.

She looked down at them. Looked up at the mirror. Looked down at the document, still open to page thirteen, with the projector lamp warm in her grip and the dual-state notation just visible in its corner under the right angle of light.

Her mother had used that symbol. She had seen it in the engineering notebooks dozens of times — in the margins of technical references, in the corner of schematic diagrams, sometimes on its own on a blank page in the middle of a notebook as though Marcelline had been working something out and that symbol was where the working-out had arrived. Dual-state conditions. Systems that existed in two simultaneous states that would normally be mutually exclusive.

She thought: what if the city was such a system.

She thought: what if she was.

On the desk beside the Accord, where nothing had been a moment before, there was a small object. A clock. Old-fashioned in its design, brass-cased with a crystal face, a style she had never seen in Meridian but which she recognized from exactly nowhere and somehow still recognized, the way you recognize things that belong to a context you haven't yet experienced but are about to. It had been left there. He had left it there, in the moment before the glass closed, in the moment when the mirror's shimmering had reached its peak.

She picked it up. It was ticking. It was warm, as though it had been carried in a pocket for a long time.

She held it for a long time in the dark and quiet of her room, listening to its unfamiliar rhythm count out a time that was not quite the same as the time her own clocks kept — slightly different, a few fractions off, as though it was calibrated to a city where the standard had been set separately from this one.

She did not sleep again until dawn was already beginning in the windows.

She did not dream. What she remembered, when full daylight arrived and she sat up and looked at the clock still on the desk where she had left it, was the exact quality of that man's eyes. Not Julian's eyes. Something older in them. Something that had been patient for a very long time and was still, at great cost, continuing to be patient.

She picked up the clock and put it in the locked drawer, alongside the paper that said Nocturne.

Then she went downstairs to breakfast and answered her father's questions about the day's schedule and ate methodically and was, by every external measure, entirely herself.

The circuit in her mind was running faster now, and the anomaly it was processing had a name, and she was not going to stop until she understood it fully.

She spent the day as she always spent days that required discretion: proceeding as though nothing unusual had happened while the part of her attention that was not occupied with ordinary functions processed the extraordinary thing that had occurred.

The man in the mirror was named Caelan Veyr. He had the same face as Julian, or nearly — the same architecture rendered in a different emotional register, with different light behind it. He had appeared in a space that mirrors did not contain and had left an object in a space he could not physically reach, which meant that whatever was happening was not a hallucination or a dream and was governed by rules she did not yet understand.

He had known about the document. He had described the second layer — or its existence, at least — before she told him about it, which meant he had access to information she had not given him, which meant either he had sources in Meridian she was not aware of or the document he had referenced in his own city was genuinely the same document and its existence in both places was real.

He had known about her mother.

Not just that her mother existed. He had said: she has been trying to reach you. Which implied ongoing effort, present tense, and which implied that Marcelline Corvayne was still capable of effort, which was not consistent with the official version of events that House Corvayne had accepted nine years ago.

She thought about this very carefully, in the way she thought about everything very carefully.

The official version was not something she had ever entirely believed. She had accepted it because accepting it was survivable and because she had been twenty-two years old — no, thirteen years old — when it happened and thirteen was too young to know what to do with not-believing. She had put the not-believing somewhere quiet and returned to it occasionally, over the years, the way you return occasionally to a room you have closed off because you are not ready to clean it out.

She was beginning to think she might be ready now.

That evening she sat at her piano — not to perform, not to practice, just to think with her hands occupied — and played for nearly an hour while she considered what she knew and what she needed to find out. The clock in the locked drawer ticked its slightly different time. She had checked it three times since putting it away, which was two times more than she had intended.

She needed to find Orin Vale again.

She needed to look at the second layer of the document with enough stability to read it properly.

She needed to understand what Caelan Veyr actually was: whether the city under the different sky was real, what the mechanism was that allowed him to appear in glass surfaces, whether the clock he had left her was a measurement device or something else.

She needed, she thought, to not sign anything for at least two more weeks.

The piano fell quiet under her hands. She sat in the near-dark of the sitting room — she had not bothered with the lamps — and let the silence settle around her and thought about her mother's handwriting in the margins of technical texts, always slightly too fast, always certain about where it was going.

She thought: I will figure this out. That was something her mother would have said. Would have said it as fact, not promise, because to Marcelline Corvayne the gap between not-knowing and knowing had always been a matter of sufficient attention applied in the correct direction for sufficient time.

She had her mother's attention span. She had always known this.

She closed the piano and went to bed and lay in the dark and thought about dual-state conditions — systems that existed in two simultaneous states — until sleep finally took her at some hour well past midnight, with the faint sound of the Nocturne clock counting out its different time from behind the locked drawer.

She woke at five in the morning — before the household, before the sky-rail's first car, in the specific quiet that belonged only to the hour before the city remembered itself. The room was grey-dark and the clock in the hall had not yet marked the next hour.

She lay still for a moment, orienting.

The man in the mirror had a name. Caelan Veyr. He had appeared once, left her an object, and told her not to sign anything. She had exactly three weeks before the ceremony. In those three weeks she needed to read the full second layer of the Accord, find Orin Vale and make him tell her what he knew about Nocturne, and understand what mechanism had allowed a man from a different city to stand in her mirror and leave a clock on her desk.

She also needed to continue being, to all external observers, exactly the person she had been before any of this happened: the well-prepared, well-composed future Lady Veyr, proceeding with appropriate dignity toward an appropriate future. This was a form of work she had been doing her whole life and she was good at it.

She got up. She dressed. She retrieved her notebook from the desk and reviewed what she had written the night before.

The list was thorough. The second list — things she did not know — was longer. This was correct. She had always found it more useful to map the shape of her ignorance than to pretend a smaller map of knowledge was sufficient.

At the bottom of the second list she had written, the previous night, in her smallest handwriting: What does he actually need from me? Not the Accord mechanics. Not the resonance access. Him personally. Why find me instead of any other Corvayne in the past nine years.

She looked at this question for a long time.

Then she put the notebook away, went downstairs, and began the ordinary morning of being Aveline Corvayne of House Corvayne, who had not had anything unusual happen to her, who was sleeping adequately, who had no particular reason to be thinking about mirrors.

The crystal bracelet on her wrist caught the morning light as she descended the stairs. She touched it once — a habit she had never quite broken, the small unconscious gesture that meant she was moving from one mode to another — and then let her hand fall, and composed her face, and went to face the day.

She was good at this. She had been good at this for a very long time. It was useful, and she intended to keep being good at it.

But underneath it, the circuit was running. The anomaly was logged. And somewhere in a locked drawer, a clock was counting out a different time with the patience of something that had been keeping time for longer than she had been paying attention.