The main hall of Chiyan Lodge smelled of cedar and old paper, and it was far too warm.

Shuohan noticed the warmth first, because it was the thing his body distrusted most. Hanjian kept its halls cold on principle. A disciple who could not think clearly in a draft was a disciple who could not be trusted in a storm. Here a fire burned in a stone hearth the size of a small cart, a brass kettle ticked on its hook, and the whole low room glowed amber, with heavy beams, a floor of worn pine boards, and shelves crowded with scrolls and jars and what looked like a chess set abandoned in the middle of a game.

A long table of dark wood ran down the center. Someone had laid out tea, rice, a dish of pickled radish, and three small cups. Someone had also, he noted, set the two chairs at the opposite ends of the table, a good twelve feet apart, with the third chair at the middle of the long side like a referee.

"I took the liberty," said Gu Chiyan, when he saw Shuohan look at them.

"It is sensible."

"I try to be. It is a failing." Chiyan set the lacquer tray with its two red candles on the sideboard, where they lay side by side like a pair of sleeping animals, and went to the head of the room to gather an enormous scroll from the shelf. "Sit, both of you. Eat if you can bear it. I find people negotiate better with rice in them."

Shuohan took the chair at the north end. The wood was cold under his hand, which was a comfort. Across the table Bai Yunzhao took the south end with a small flourish, adjusted his sleeves, and poured himself tea with the unselfconscious ease of a man in his own house. He did not look at Shuohan. He was very carefully not looking at Shuohan, which was louder than looking.

Shuohan did not eat. He sat with his hands flat on the table and watched the officiant unroll the scroll.

It was long. It was the length of the table and then some, and Chiyan had to weigh down the far end with the teapot. The paper was the color of weak tea, dense with columns of old characters in black ink, and over the top of it, in red, in a hand so ancient the strokes had half faded, ran a single heading.

"The Terms of the Candle," Chiyan read aloud, in a voice that had lost its playfulness. "Set down by the first bearers, in the first year the swords were reunited. Copied by me, from a copy of a copy, because the original crumbles when anyone breathes on it. I will read it plainly, and I will answer any question you put. I will not answer questions twice."

"Begin," said Shuohan.

"One. The bearers of the two blades shall join in a vow before witnesses, with red candles lit between them. The vow is binding for one hundred nights."

"Binding in what sense?" Shuohan said.

Chiyan paused, finger on the line. "In the only sense the text allows. The candles are the vow. Their flame is its body. As long as the flame is kept, the vow stands."

"And if the flame is not kept?"

"We are coming to that."

"We are coming to it now."

He heard how it sounded. Across the table, Yunzhao's mouth moved at one corner, and Shuohan felt a flat, dull irritation at having been amusing without meaning to be. He did not look away from the officiant.

Chiyan sighed, theatrically, and continued. "Two. At every sunset the bearers shall together light a pair of red candles in the candle room, and the candles shall burn until the first light of dawn. They shall not be lit by one hand alone. They shall not be snuffed, shielded, or relit by any other. They shall burn through the whole of the night."

"A pair of candles each night," Shuohan said. "A hundred nights. Two hundred candles."

"Two hundred and one. The first night's pair is the ceremonial pair, and it is thicker." Chiyan nodded toward the sideboard. "Those. Tomorrow."

"Tomorrow." That was new. "The letter said the ceremony was three days from the date of writing."

"It was. You are a day early, both of you, which I take as a sign of either diligence or dread." Chiyan smiled at them in turn. "Tonight you will sleep in the guest wing, apart. Tomorrow at sunset we begin. I thought a night of ordinary rest might be good for your tempers."

Shuohan looked at the pale, delighted face of the man at the far end of the table, who had already begun to stir sugar into his tea, and thought that a night of ordinary rest would do very little for his own temper.

"Three," said Chiyan. "For the hundred nights, the bearers shall dwell beneath one roof and shall not remove themselves from it for longer than half a day's walking at a measured pace. Should the bearers be parted by more than that, the vow weakens, and the swords call to one another across the distance and drink of the bearers to make up the lack."

"So that is why my master died," Yunzhao said, softly. It was the first thing he had said in several minutes, and it did not sound like a joke. "The swords were kept apart."

Chiyan's eyes went to him and stayed for a moment. "It is one of the reasons," the officiant said. "The text is not exact about the rest."

Shuohan had not realized he had turned his head until he found himself looking at Yunzhao directly, and found Yunzhao looking back. For a fraction of a second the smile was gone. The man across the table had a narrow, tired, watchful face with nothing arranged on it at all. Then the smile came back, like a lamp being lit in a window, and Yunzhao reached for the pickled radish.

Shuohan looked at the scroll again, and found that his thumb had been moving along the edge of the table, back and forth. He made it stop.

"Four," Chiyan went on, more briskly. "The bearers shall keep their blades near. The blades shall not be sheathed in the candle room while the flame burns. Five. Neither bearer shall extinguish the flame in anger, nor by neglect, nor by the nursing of any grudge. The flame answers to the heart, and a grudge is a draft."

"That is poetry," said Shuohan. "It is not a rule."

"It is the oldest rule in the document," said Chiyan, "and the one most likely to ruin you both. I would take it seriously."

He let that sit. A log shifted in the hearth, and a spray of sparks went up the flue.

"Six. Should the flame fail in the night, whether by wind, by hand, or by a failure of the vow, that night is void. Every night counted up to that morning is likewise forfeit, up to the number of seven. And the swords..." He cleared his throat. "The text says the swords shall wake."

"Wake," said Shuohan.

"The curse, I think. The old words are very dramatic."

"How many nights are forfeit if the flame fails on the first night?"

"None, I suppose. You would not have seven to lose. But I would not recommend it as a strategy."

"Seven nights," Yunzhao said thoughtfully, tilting his cup. "That is generous, as these things go. I had expected the whole account."

"The whole account would be a cruelty," said Chiyan. "The first bearers were not cruel, only frightened. Seven nights is a mercy, and a warning. The seventh night, it is said, is the one on which the bond is hardest to hold."

Shuohan filed that away in the cold part of his mind where he kept the things he intended to use. Seven nights. A hundred nights. A man who could not hold a candle for a week would have no business with a hundred.

He asked about the wording of the fifth clause, and Chiyan answered. He asked what counted as a shield against wind, and whether a closed door was a shield, and Chiyan said a door was a door, and the wind was the wind, and a candle in a house was not forbidden to be indoors. He asked whether the bearers might sleep in separate rooms, and Chiyan looked at him with an expression of grave, almost tender regret.

"There is one candle room," the officiant said. "There is one bed in it."

The silence that followed was long enough to hear the kettle.

"One," said Shuohan.

"The lodge was built to hold a ritual, not a household. The candle room is the center of it. The bearers must be near the flame, and the flame must be within sight of both of them for the length of the night. There are three other rooms in this building, a kitchen, a storeroom, and this hall. I regret the arrangement. I did not design it."

"What a mercy for the thrifty," said Yunzhao, and sipped his tea. "One bed. Think of the savings on linen."

"Do not," said Shuohan.

"I have said nothing."

"You are about to."

"I was only going to observe that we are a pair of grown men with a hundred nights ahead of us and a bed built for one very patient sleeper. I thought we might draw lots." Yunzhao's eyes were bright. "Or fight for it. I would enjoy that. I have never been allowed to fight you for anything useful."

"I will take the floor."

"You will freeze."

"I am used to it."

"That is not the point I was making."

Shuohan made himself breathe. He had not come here to be teased by a man who talked as other people breathed. He had come because the thing in his left hand was frost, and because a dead man in the snow deserved better than this boy's careless wit. He turned back to Chiyan.

"You said the swords drink of the bearers. You said the old words are dramatic. I want to see what you are not telling us."

Chiyan did not reply at once. He took a long, slow sip of his tea, set the cup down with a small click, and then, rather as a man pulls a bandage, rose and went to the sideboard. He came back with two long bundles wrapped in white silk and laid them side by side on the table, on the unrolled scroll, so that the two ends of it lay on either side of them like folded wings.

"Draw them," he said. "Halfway. Not all the way. And lay them on the silk."

Shuohan stood. The bench scraped. He crossed the length of the hall until he was beside the bundle at the northern end, and he drew Hanxue from its sheath with a long slow motion, until six inches of pale blade showed in the firelight. Frost climbed the steel at once, in ferns, up from the guard. At the other end of the table Yunzhao rose in a rustle of white and pale blue and did the same with Taoying, and the blade that came out of that sheath was the color of dawn, rose and gold, the faintest blush on steel.

They laid them down. The two swords lay on the silk with their hilts toward the ends of the table, their half-drawn blades pointing toward each other across the document, and for a moment nothing happened.

Then Hanxue began to hum.

It was the same sound he had heard in his room on Hanjian, low and clear and aching, like a struck glass. And from the blade across the table came an answering tone, higher, sweeter, bell-like. The two notes met above the scroll and wound around each other, and Shuohan felt the hairs rise along his arms.

"Look at the steel," Chiyan said quietly.

He looked. Along the flat of Hanxue, beneath the frost, ran a hairline of darker grey, a thread of corrosion no thicker than a spider's silk. It started at the guard and ran along the blade almost to the point. He had never seen it before. He had polished that blade a thousand times.

"On Taoying also," said Chiyan, and Yunzhao, who had gone quite still, turned his own blade slightly in the light. There was a line of the same dull thread along the rose-colored steel. "The old masters called it the thirst. It is where the curse lives in the metal. On a bearer who loves the blade it spreads slowly. On a bearer who hates the other half, it spreads quickly. And on a bearer who does not know what he carries..."

"My master," Shuohan said.

"Both of your masters." Chiyan's voice had dropped, and all the lightness was gone out of it. "I have seen the blades of both. I was permitted to see them before they were returned to their sects. The marks were the same. The progress was the same, to the day. Hanjian's master and Qingyun's master died within the same three months of the same winter, of the same slow wasting, and neither of them knew that the other was dying." He stopped. "That is not a coincidence. That is the sword."

Shuohan stood very still.

He had known that his master died of the curse. He had known it the way a man knows a fact written in a book. He had not known that someone else, on the far side of the mountain, had died in the same hour, in the same way, and been mourned by someone else just like him. Across the table, Yunzhao's face had gone slack with something raw and unguarded, and for the first time Shuohan understood that the man had a grief of his own, which was not a weapon, and which had nothing to do with him.

He did not want to understand it. It was simpler without.

"Then someone sent the petal," he said, and he heard his own voice come out harder than before, as if he had put a hand to a wall and felt it hold. "Someone laid a peach blossom on my master's body. Qingyun's mark, left where I would find it. If your sect also lost a master, you may call that a grief. I call it a very convenient sorrow."

"I beg your pardon?" said Yunzhao.

He had not raised his voice. He had said it very softly, and the softness was worse. Frost bloomed along the flat of Hanxue, an inch at a time, as the blade began to shake.

"A flower," said Shuohan. "In the throat of a dead man in the snow. You will tell me that was nothing. That a blossom blew in from the south and happened to alight on my master's body."

"I will tell you," said Yunzhao, "that peach blossoms grow in the valley where I was raised and nowhere else within two hundred miles, and that anyone who wished to cast suspicion on Qingyun would have to be an idiot or a very clever man, and I do not think that you are an idiot." His smile was gone entirely. There was only a pale, controlled, furious face. "Do you imagine I carried a sack of petals up your mountain? Do you imagine my master, who could not climb a flight of steps in his last month, went to Hanjian to murder yours?"

"I imagine that someone left a flower."

"And I imagine that the man who accuses a dead enemy of leaving flowers has been angry for a very long time, and has not stopped to ask who else might have known that it would work."

The words struck somewhere low, and Shuohan felt it. It was the tone of a man who had also been asking the question for years, in the dark, and had arrived at the same answer from the other side.

Taoying lit.

Not with flame. With petals. They bloomed along the half-drawn blade, one and then another, translucent pink and white, forming out of the air itself, drifting up from the steel in a slow spiral and scattering across the table. A cold wind went through the room. Hanxue answered it with a hard bright crackle of ice, and in a moment the whole length of the table was strewn with frost and blossoms, the two things warring in the firelight, and the teacups rang on their saucers, and the fire in the hearth guttered low.

"Enough," said Gu Chiyan.

He did not say it loudly. He had stepped between the two ends of the table without either of them seeing him move, and he laid one palm flat on each blade, as a man might calm a pair of horses. The humming stopped. Frost and petals hung in the air for a moment longer, then fell. The fire steadied.

"You are going to do this every time," the officiant said, with a gentleness that cost him effort. "Every night you will lose your tempers and the swords will take your tempers for food. And on some night, if you are not careful, you will do it at the wrong hour with the candle between you, and it will go out. You may hate each other. I have no quarrel with that. People have lived and died on less. But you will do it quietly, and you will do it with the door shut and the flame protected, or you will die of it, and I will have wasted a very good winter."

Neither of them said anything. Yunzhao's chest rose and fell. Shuohan stared at the table, at the tiny petals melting in the heat of the fire and the frost crawling slowly away across the wood. He was aware of a hot, stupid shame he could not account for. He was aware, too, of the odd sensation that he had been very close, for a moment, to something, and had turned away.

"Sit," said Chiyan. "Please."

They sat.

"Seven," said the officiant, after a minute, in a voice that was almost back to normal. "After the hundredth night, if the flame has held, the blades shall be bound to one another, and the vow shall be fulfilled and dissolved. The bearers may then go their ways. That is the last clause. There are some appendices on diet which I will spare you."

A short, unwilling huff of laughter came from the south end of the table. It was Yunzhao, who put a hand over his mouth and looked, for the first time all evening, rather like a boy.

"Forgive me," he said. "Diet."

"Mostly broth," said Chiyan. "The first bearers had a great deal of faith in broth."

The tension ran out of the room like water out of a cracked jar. Shuohan found that his hands were shaking slightly and put them under the table.

Chiyan went to the sideboard and returned with an inkstone, a brush, and a small porcelain dish of vermilion, thick and bright, the color of fresh blood. He set them on a sheet of red paper, a single page, bordered in gold, with eight lines of characters beneath a painted peach branch.

"The agreement," he said. "Your names, your sects, your assent. It is a formality. The candles do the real work. But I am a man of paperwork, and I will not be argued out of it."

Yunzhao rose. He crossed the room in three easy strides, took the brush from the dish, and without reading the page, without so much as a glance at Shuohan, signed his name in one fluid line. Bai Yunzhao. The strokes were quick and clean and carelessly beautiful. He laid the brush down, and looked up with a bright impudent smile.

"I have never been troubled by a contract," he said. "It is the clauses that make the trouble."

Shuohan stood. The page lay on the table with the red wet gleam of the signature on it, and he looked at it for what felt like a long time.

It was a very small thing. A name. He would write it with a brush in a hall by a fire, and in the morning it would be a fact, and in a hundred nights it would be over. He had signed a hundred documents in his life. He had signed the one that made him his master's heir. He had signed the one that made him a captain of the outer guard. Never once had his hand felt as heavy as this.

He thought of Lin Wei's flinch. He thought of an old man's open eyes under the plum trees.

He took the brush.

Ling Shuohan, he wrote, in the plain square hand of Hanjian. It looked like a stranger's.

"There," said Chiyan, and blew on the ink. "That was not so terrible."

"It was a little terrible," Yunzhao said, and caught Shuohan's eye, and for once did not look away at once.

"The rules of the house," said Shuohan, because it was easier to speak of rules than of whatever that was. "Before we part for the night. I will state them. You will agree or not."

"I am all attention."

"We are bound by the clauses and no further. We do not share beds beyond what the candle requires. We do not touch except by necessity. We do not speak of our masters. We do not discuss the sects."

"You have thought about this."

"For three days."

"I am flattered. I have thought about nothing for three days but my horse." Yunzhao considered him, head a little to one side. "I accept. The terms are acceptable. We shall be as two very polite pieces of furniture, sharing a house."

"A truce," said Shuohan.

"A truce. In name." The brightness in his eyes did not fade. "Though I confess I would pay to see whether furniture can sustain it for a hundred nights."

Chiyan clapped his hands once, softly, and rose. "Wonderful. I knew you had it in you. The guest wing is across the courtyard, two rooms, lamps already lit. I shall tend the fire. Sleep, both of you. Tomorrow you will need your strength."

They went out in silence into the courtyard, where the snow had begun to fall again, in a fine soft powder that glittered in the light of the old red lanterns. Shuohan walked three paces ahead. He heard Yunzhao behind him, the faint brush of white silk, and then a pause, a small stop and start of footsteps, and Chiyan's quiet voice from the hall doorway, saying something too low to follow.

He turned.

The officiant stood on the threshold with the firelight at his back, one hand extended. Yunzhao stood in front of him, his own hand lifted to meet it, and between their palms, for the space of a single breath, something small and dull and yellow caught the lantern light and winked.

A key. A short, heavy key, made of old brass.

Then Yunzhao's fingers closed over it, quickly, quicker than any ordinary man would have thought to move, and slid it into his sleeve. His face, turned a little toward the light, was perfectly smooth. When he saw Shuohan watching, the smile came on at once, wide and warm and entirely without cracks.

"What?" said Yunzhao.

"Nothing," said Shuohan.

He turned and went on across the snow. Behind him he heard Chiyan close the hall door, and Yunzhao fall into step, whistling something tuneless under his breath. Shuohan did not look back. He walked to the guest wing with his thumb moving slowly along the hilt of Hanxue, and he thought, with a cold and careful clarity, that he had signed his name to a vow and sat down at a table with a man who had a secret, and that he had been, until very recently, a person who found such things easy to forgive.