Greta Thornquist arrived at the vault at ten o'clock with five auditors, a locksmith, a camera crew from the Foundation's own communications office, and a box of doughnuts.

Dilly counted them as they came off the stairs, because the stairs were the only way down. Five in grey suits with lanyards. The locksmith, a thick man in a canvas apron. The camera operator, walking backwards. Greta last, in a camel coat with a Foundation pin on the lapel, those famous Odessa cheekbones cutting the lamplight into planes. She carried the doughnuts herself, in a white box with a ribbon, the way another woman might carry a baby she meant to be photographed with.

"Margit," Greta said. "Dear. I do hate that it has come to this."

Margit stood in front of the vault's central desk in her grey wool. Her hands were folded. She had been standing like that since half past nine, when Dilly had come down the stairs and found her already there, and had said nothing about it, and had stayed.

"Good morning, Ms. Thornquist," said Margit. "Which part has come to what?"

"The audit." Greta set the doughnuts on the nearest deposit box with a little flourish. "The board has voted, you'll have been told. Nine to two. It's all quite proper. Fairhold's reserves have not been verified by outside eyes since the founder's retirement, and with her gone and a new Keeper unmarried and, forgive me, unwell," she glanced at Dilly, not quite at her, "we simply cannot be seen to leave the books alone."

"The books are verified every night at eleven fifty-eight."

"By the family."

"By the Clerk."

"By the Clerk, then, who is employed by the family." Greta smiled. It was a beautiful smile. It reached her cheekbones and stopped. "I've brought the order. You may read it."

She held out a folded paper. Margit did not take it. Dilly did, and read it standing, with her thumb on the seal. Three paragraphs, a Foundation letterhead, Maurice's signature in blue pen, a looping M like a pair of wings. She read the operative sentence twice.

"It says you may take 'all ledgers, registers, and records stored in the vault for the purposes of imaging and verification, to be returned within twenty-four hours.'"

"That's right."

"The ledger is on that desk." Dilly kept her voice flat. "The black one. It has to be there at eleven fifty-eight tonight."

"And it will be, if we are quick." Greta's smile did not move. "It's not a mystery, dear. Our people photograph each page. They hand the book back."

"Within twenty-four hours."

"Well, that's the formula."

"Which means anywhere between now and tomorrow morning." Dilly folded the paper along its crease. "Tonight is Thursday. If you're holding the book at eleven fifty-eight, there's no signature, and if there is no signature..."

"Then regrettably the stake falls to the Foundation." Greta tilted her head. "But why would I do such a thing? That would be improper. I only want the books."

The locksmith shifted his weight. The camera operator, a boy of about twenty-three with a nervous swallow, looked at Dilly with the face of someone who had not been told what job he was on. Dilly looked back at him until he lowered the lens a few inches.

"Margit," she said. "What does the Founder's Rule say about records?"

"That no officer, executive, or member of the Foundation may examine an individual's account without written consent or a court warrant." Margit did not move. "It says nothing of the Clerk's own register. The Clerk's register is the Clerk's."

"And the black ledger?"

"Is the Keeper's. In my custody when he is absent, in his when he is present. It was never Foundation property." A pause, precise as a coin on a counter. "Ms. Thornquist knows this. She has read the trust."

"I have," said Greta lightly. "I've also read the clauses on incapacity, and on fraud. Counsel would argue that a ledger signed by a man with a, a health problem."

"Counsel may argue," said Margit, "in the morning. After the Close."

"Perhaps." Greta turned a hand palm upward. "Or perhaps I'll simply sit here and eat a doughnut while we all wait for him to be late."

It was, Dilly thought, rather well done. The doughnuts were the finishing touch. A woman who brought pastries to a siege could not afterwards be described by anyone as having been unreasonable.

She made her decision in the time it took the camera operator to swallow.

"Here is what happens," she said. "Your people image every page of the black ledger in this room. On this desk. With Margit watching every sheet. It does not pass that door. Nobody touches the stamp pad or the pen or the inkwell or a single deposit box. The locksmith goes upstairs. The camera goes upstairs." She turned her head. "And you stay at the foot of the stairs, Ms. Thornquist, because I would like to see how you eat that doughnut standing up."

"Dilnoza." Greta laughed. "We're not at war."

"Then it won't hurt."

Greta's eyes narrowed a fraction, which was the only time Dilly saw the real woman come to the surface of the water. Then the smile closed over it. "Very well. The ledger on the desk. Though I will take the previous volume with us. The one in the cabinet, covering my aunt's years after her husband's. That doesn't sit on any desk."

Margit's head came round.

"No," Margit said.

"I've seen the inventory." Greta opened her bag, drew out a clear plastic evidence sleeve the size of a bread bin, and unfolded it with a snap. "Twenty-four hours. It's a book."

"It is a book," said Margit, "with Odessa's handwriting in it."

"Which is exactly why we need it."

The two women looked at each other. Dilly had never seen Margit lose a staring match, and she did not lose this one; but she did something harder, which was to blink, and step aside from the cabinet, and say in a voice with no exclamation mark anywhere in it, "The key is on my ring. You will not hurry the lock."

* * *

It took them an hour and forty minutes to image the black ledger. Dilly stood at the desk the whole time with her arms folded, and Margit stood across from her with her hands folded, and the auditors turned the pages one by one under a ring of white light and murmured to each other like surgeons. Greta ate her doughnut at the foot of the stairs. She finished it. She took a second, which Dilly noted as a small tactical error.

The old volume went into its sleeve and up the stairs at 11:40, and when the plastic closed over its spine, Dilly had a clear and unwelcome picture of a pair of thin old hands signing it night after night in a room with one lamp.

She had used the time. Every page the auditors turned she had photographed over a shoulder, a thumb on the shutter, the phone held low against her hip like a woman checking a text. It was a stupid risk and the only one she could think of. It was not until the footsteps had faded, and Margit had sat down, very slowly, in the visitor's chair, that she looked at the pictures properly.

Beside the signatures, in the narrow outer margin, in very faint pencil, there was a small tick.

Not on every page. On some. A tick, and sometimes a date, and sometimes a single initial. She zoomed in with her thumb. They were not Odessa's. Odessa wrote with a pen like a blade. These were small, upright, quite unemotional. A clerk's marks.

"Margit."

The older woman did not answer.

"These are yours."

"Yes."

"What are they?" She turned the phone. "This one is March the eleventh. The lock cylinder." She scrolled. Her own pulse was slow and loud. "You told Sel you hadn't told him about the winter. You never said you'd been keeping a record."

"I said I had not told him. I did not say I had not written it down." Margit looked at her hands. "Odessa asked me to. She said, Margit, if a thing is done to my Close, you will mark it, and you will tell no one until I say. And she died before she said."

"How many ticks?"

"Fifty-one."

"Fifty-one." Dilly thought of the winter. The elevator twice, the taxi once, the lock. Four. "That's not four. That's fifty-one nights somebody tried to make the Close late."

"Small things, mostly. A card reader that would not read. A pen with a dry nib. A key that stuck. A clock that was a minute out." Margit's voice never altered. "I fixed what I could. I did not report them, because Odessa said not to. The loud ones I wrote in the incident book, and they frightened me. The ticks are the small ones." She lifted her eyes. "I did not understand that they were all one thing until I saw them together in a column."

"Where do the small ones begin?"

Margit was silent for a long moment. Then she took off her reading glasses, folded them, and put them away.

"The first page you photographed," she said. "Look at the date."

Dilly swiped back to the start. The earliest tick sat in the top corner of a page near the front of the live volume, small and upright, and beside it, in the same grey pencil, a date.

11 FEB.

She looked at it for some time. The brass lamp ticked as the metal cooled. Far above them, in the tellers' hall, a door swung shut and somebody laughed.

"The Ventura launch," she said.

"Yes."

"The same day I..." She could not finish it. It was ridiculous, how ordinary the room stayed, with the lamp and the green leather and the smell of ink.

"The same day," said Margit. "Odessa was the one who noticed. She said, there is a coincidence in this, Margit, and I do not care for coincidences. They are what clever people call a plan they have not yet seen the whole of." Her flat voice was gentler than Dilly had ever heard it. "That is why she sent for the Karimova girl. She did not think you were a mistake. She thought you were the first move."