The letters from Varath arrived on a Tuesday, a little before the second bell.

There were seven of them, bundled with the red ribbon of urgent classification, which meant that someone in the southern regional office had decided the contents could not wait for the weekly compilation. The decision was correct. Naia read the first letter standing at her desk with her coat still on, read the second with one arm out of its sleeve, and sat down to read the remaining five without ever finishing the business of taking the coat off.

The Fading in Varath had doubled in twelve days.

Not risen. Not quickened. Doubled. In twelve days, the number of citizens reporting blank wrists in the southern territory had gone from following the pattern she had mapped to exceeding it by a factor that the regional scholar described, in the third letter, as without precedent in thirty years of observation. It was the kind of phrase that scholars who had spent thirty years watching something did not use lightly. Naia read it twice. Then she laid the seven letters across the desk in sequence and began to build the picture they made together.

It was not uniform. The acceleration was concentrated in the coastal districts, the densest and most devout. In Varath, finding one's Registry match was not merely expected, it was celebrated. The port festivals had built entire rituals around the public acknowledgment of a new Bond: garlands hung from the harbor lamps, a night of lanterns on the water, a bell rung from the customs house for every couple who stood up and spoke their names aloud before the crowd. A city that had built so much of its public life around the Registry could not hide it when the Registry failed. It failed visibly, in the market and on the quay, and no official statement about ongoing investigation could cover that.

The sixth letter was shorter than the others and was written in a different hand, a nervous, rounded script that pressed too hard into the paper. It was from a registrar in the old merchant quarter. It said that the bell at the customs house had not been rung in nine days. It said that the harbor garlands had been taken down by the lamplighters without anyone asking them to. It said, in a final line that the registrar had underlined and then, apparently, thought better of and scratched halfway out: People have started to look at each other's wrists in the street.

Naia put the letter down very carefully.

She was in the middle of drafting the emergency request for a field investigation when Lena appeared in the doorway.

"The senior scholars have the Varath letters," Lena said, in the tone of someone delivering news she suspected was not news. "There is a meeting called for this afternoon. The council chamber, the fourth bell."

"I know. I am writing the proposal now."

Lena came in and looked at the spread of paper without touching it, which was how she looked at Naia's desk when she wanted to read something without being seen to help herself. Her face changed as she read. The cheerfulness that lived in it went somewhere deeper and quieter, and for a moment she looked her real age, which was a fact Naia sometimes forgot.

"It is worse than the preliminary counts," Lena said.

"Considerably."

"What does it do to the timeline?"

"It ends it." Naia set down her pen. "The regional scholars are good, but they work inside the standard protocol. What is happening in Varath needs someone to stand in it. Someone who can ask the questions the protocol does not allow."

"You are going to propose a field investigation."

"I am going to propose the only response the data supports."

Lena sat in the chair across the desk, the one she had been occupying uninvited since her second week in the Wing, and did what she did when she had something to say and had not decided how: she looked at the ceiling, then at her hands, then at Naia. "Are you going to propose going alone? Or with the Commander?"

"The mandate is joint. I do not have the authority to decide otherwise."

"That is not an answer to the question."

Naia returned to the page. "The joint mandate is the correct structure for this investigation. Two investigators with different methods give better coverage of a complex situation than one."

"Absolutely," said Lena. "That is certainly why."

"Lena."

"I did not say anything."

"Your silence said several things."

"My silence was professionally appropriate." Lena stood and smoothed her robe, which had a smear of ink on the left cuff that she had not noticed. "Is there anything you want pulled from the archives before the meeting?"

"The records of the last deceleration event. Forty years ago. I want to know whether the geography then resembles the geography now."

"Done." Lena paused at the door, one hand on the frame. "Naia. The bandage."

"What about it?"

"Nothing. Never mind. I will get the archives."

She went. Naia stared at the closed door for some time before she realized she had been looking at it with her right hand resting over her left wrist, and she lifted the right hand away as though it had been caught somewhere it did not belong.

The council chamber on the first floor had better acoustics than the second-floor hall and worse light. It was a long room with a coffered ceiling, high narrow windows on the north side, and a table of dark wood that had seen the signing of three centuries of Registry reforms. Lady Verun was present, as she was present at most things that mattered in this building, positioned at the right side of the table where she could watch both the speaker and the larger part of the audience in a single sweep.

Commander Kairu was already in the room. He had taken a place against the back wall, as he had in the second-floor hall: best angle, widest view, no profile offered. He did not acknowledge her entrance, and she, with some effort, matched him.

She presented the Varath situation in twelve minutes, which was the time it took to say what needed to be said and nothing else. The doubling. The geography. The cultural context that made the southern Fading more visible than the northern numbers, which were larger in total but spread across a population that kept its Registry more quietly. She did not read the registrar's last line aloud. She thought about it. Then she decided that some things were not data.

The questions came faster this time, sharper, and more afraid. She had noticed over the years that fear made questions more honest. When there was no real urgency, people asked the questions that served their interests. When urgency arrived, they asked what they actually needed to know.

"A field investigation," said the senior scholar from the eastern desk, trying the phrase for weight. "In Varath specifically? Or the southern corridor?"

"Varath first. The coastal districts have the fastest acceleration. We need direct observation before we can say whether the Fading is spreading from a point of origin or breaking out everywhere at once."

Lady Verun spoke for the first time, and she spoke to the back of the room. "Commander Kairu. Your assessment of the security requirements."

"A standard escort to Varath, three days' travel," he said. His voice did not rise to carry; it simply arrived. "Requirements at destination depend on the scope of interviews. I recommend flexibility in the plan rather than a fixed schedule, given how quickly the situation is changing."

"And you are available for the duration?"

"Yes."

Lady Verun turned. "Scholar Solven."

"Also yes."

"Then it will be arranged." She wrote something in her notebook. "Within three days, I think, given the rate of change in the south."

It was over in less time than it took to describe. Naia gathered her papers, aware as she did so that she had just agreed to spend the better part of two weeks in close company with a man who had, in the space of a few days, found two flaws in her best work, repeated her own thoughts back to her more clearly than she had said them, and stood at her window at midnight describing a Tower in terms she had not known anyone else possessed. She did not name any of this as a problem. She wrote down the departure date.

In the corridor afterward, Reth was waiting with a logistics folder and the expression of a man who had begun solving the problem before it had officially become one.

He was a broad, weathered man, a few years older than the Commander, with a face that people called cheerful until they had worked with him long enough to notice that cheerful was not the word. Alert, perhaps. Awake in a way that most people were not. He fell in beside Daven with the ease of six years' habit and opened the folder as they walked.

"Varath," he said. It was not a question.

"Varath," Daven confirmed.

"Three days each way. Four to six on the ground, depending. Escort of four. Quarters at the regional Registry office at first, shifting to the government quarter if it runs long." He flipped a page. "The handbook has a protocol for coordination assignments that touch the Oath. I have flagged it."

"That is not necessary, Reth."

"The handbook requires acknowledgment before departure."

"Then acknowledge it on my behalf."

"The handbook requires the acknowledgment to come from the oath-holder."

Daven looked at him.

Reth returned the look with the serene expression of a man citing a regulation that he had personally drafted for exactly this occasion, which he had, and which was written in plain print on page forty-two. It was the kind of small insubordination that only a man who had earned an enormous amount of trust could afford.

"The Oath may be released in two ways," Daven said, in the flat recitation of a man reading a clause aloud. "By the holder's own determination that his service is complete. Or by a direct order of the Emperor. A field investigation does not constitute grounds for either. The Oath remains in force."

"Noted for the record."

Naia, passing through the corridor with an armful of files, caught this exchange at a distance of about eight feet. She did not slow. She did not look at either of them. It was administrative information, and she filed it under relevant context, and she did not ask herself why she had listened to the second condition twice in her head all the way to the stairs, as though it were an equation with an unexpected term in it.

An order of the Emperor. She was not quite sure why that phrase made her uneasy. She put it away.

She spent the next two evenings preparing. There was a great deal to pack. The deceleration archives. The Varath letters. The Mirehn logs, which the Commander had delivered on Wednesday as promised, in the early afternoon, accompanied by a note in his small hard hand that said only, Margin included. Her notebooks. Her instruments. Three changes of plain robes. A lamp with a shade that did not rattle.

Lena helped, with the frank energy of a person who intended to be useful and mildly intrusive in equal parts.

"You are packing nine books."

"They are references."

"The carriage has a single table. You will not open nine books in four days."

"I will open as many as the evidence requires."

"You will open three and carry six," said Lena, and removed a volume from the pile with the tact of a woman removing a knife from a toddler. "Are you traveling with the Commander the whole way?"

"The mandate is joint."

"Yes. I heard." Lena folded a robe in thirds. "He took a carriage for himself last time he went south. A single, with the escort."

"This is a different assignment."

"It is a very different assignment," Lena agreed, and then she saw Naia's face and had the grace to fall silent, and the folding went on without commentary.

On the second evening, when the trunk had been strapped and the lists checked twice, Lena produced a small flat tin from the pocket of her robe and set it on the desk with the offhand air of a person returning a borrowed pen.

"For the road," she said.

Naia opened it. Inside, wrapped in waxed paper, was a measure of the dark smoky tea she drank when she was working through a problem and did not want to be disturbed. It was not sold in the palace. She knew because she had once asked, and been told that no one had ordered it in a decade.

"Where did you find this?"

"There is a shop near the south gate. The owner thinks I am eccentric." Lena shrugged. "The way-houses on the southern road will have only the common blend. You hate the common blend."

"I do not hate it. I find it insufficient."

"That is how you hate things." Lena gave her a brief, fierce smile. "Make it strong. Sleep occasionally. Write to me if the sea is as ugly as people say."

Naia held the tin for a moment longer than was necessary. She had been given gifts before, mostly by people who had wanted something. This was the first she could remember that had been chosen entirely for the sake of her comfort, and she did not know what the correct response was, so she settled on the true one.

"Thank you, Lena."

"You are welcome." Lena was already at the door. "That was very nearly easy."

"Do not let it go to your head."

"It is far too late for that," said Lena, and went out whistling something out of tune.

The night before departure, Naia sat alone in her office after Lena had gone home. She had told herself she was checking her lists. The lists were done. She turned off the main lamp and sat in the dark with the window open, and looked at the Tower.

It was dimmer than it had been the week before.

She did not need an instrument to know it. She had been watching it for years, long enough to have learned its small moods, its way of brightening a little after rain, the faint flutter at the top of the spire in a high wind. The gold was thinner now across the whole height of it, and the lowest courses, the ones that had always seemed warmest, had begun to take on a color closer to ash than to sun.

She wrote this down in the notebook she kept for the purpose. She dated it. She noted the hour. It was a data point and she handled it like one.

She did not note that the room felt very large and very quiet. She did not note that she had been sitting for a quarter of an hour without turning a page. Her wrist lay on the windowsill under the cloth, and she did not look at it, and the not-looking was so complete and so deliberate that it was almost a kind of looking.

Tomorrow she would leave this window. For the first time in eight years she would not be able to see the Tower from her desk.

She was surprised to find that she minded.

The carriage assembled in the palace's southern yard before sunrise, in the grey light that came before the first bell. Cold air smoked off the cobblestones. Horses shifted and blew in their traces, and the escort, four men in the dark uniform of the Guard, stood at their stations without talking, the way soldiers did before a journey, each looking at nothing in particular.

Daven was already there.

He stood by the carriage door with a folder open in one hand, reading, in the pose of a man who had been standing in this exact spot for some time. She checked the angle of the sky and the position of the lamp on the carriage and made a quick estimate: he had been there at least five minutes. Perhaps ten.

She did not ask why. He did not offer. He looked up as she approached, took in her single bag and her armful of files, and without a word took the files from her and set them inside, on the left-hand seat, where she would be able to reach them.

"Scholar Solven."

"Commander."

"The road is dry. We should make good time."

"I am glad to hear it."

That was all. He handed her up. She took her seat on the left-hand bench. He took the right. Reth swung up beside the driver and rapped twice on the roof, and the carriage lurched forward and began to roll.

They passed through the yard gate and out into the street, where the lamplighters were still making their rounds and the first bakers were pulling their shutters up. Naia looked out of her window. He looked out of his. The folding table between them was clear, the files stacked on the seat, and the space inside the carriage was smaller than the council chamber and larger than her office, a middling space, and for the length of the first street neither of them said anything at all.

Behind them, over the rooftops, the Tower stood in the grey dawn, still lit, still thin. She watched it through the little rear glass until the road turned and it slipped out of sight.

When she faced forward again, she found that Daven was not looking out of his window anymore.

He was looking at his folder. It was open to a page. She thought it was the same page it had been open to at the yard, and the one before that.

She turned back to her own glass, and they went south.