YOU WERE NEVER FAR from the sea in Cádiz. The smell of it was always there, almost as powerful as the stink of sewage. On the city’s southern side, when the wind was high and from the south, the waves would shatter on the sea wall and spray would rattle on shuttered windows. After the battle of Trafalgar storms had battered the city for a week and the winds had carried the sea spray to the cathedral and torn down scaffolding about its unfinished dome. Waves had besieged Cádiz and pieces of broken ship had clattered on the stones, and then the corpses had come. But that had been almost six years ago and now Spain fought on the same side as Britain, though Cádiz was all that was left of Spain. The rest of the country was either ruled by France or had no government at all. Guerrilleros haunted the hills, poverty ruled the streets, and Spain was sullen.

February 1811. Nighttime. Another storm beat at the city and monstrous waves shattered white against the sea wall. In the dark the watching man could see the explosions of foam and they reminded him of the powder smoke blasted from cannons. There was the same uncertainty about the violence. Just when he thought the waves had done their worst, another two or three would explode in sudden bursts, the white water would bloom above the wall like smoke, and the spray would be driven by the wind to spatter against the city’s white walls like grapeshot.

The man was a priest. Father Salvador Montseny was dressed in a cassock, a cloak, and a wide black hat that he needed to hold against the wind’s buffeting. He was a tall man, in his thirties, a fierce preacher of saturnine good looks, who now waited in the small shelter of an archway. He was a long way from home. Home was in the north where he had grown up as the unloved son of a widower lawyer who had sent Salvador to a church school. He had become a priest because he did not know what else he should be, but now he wished he had been a soldier. He thought he would have been a good soldier, but fate had made him a sailor instead. He had been a chaplain on board a Spanish ship captured at Trafalgar and in the darkness above him the sound of battle crashed again. The sound was the boom and snap of the great canvas sheets that protected the cathedral’s half-built dome, but the wind made the huge tarpaulins sound like cannons. The canvas, he knew, had once been the sails of Spain’s battle fleet, but after Trafalgar the sails had been stripped from the few ships that had limped home. Father Salvador Montseny had been in England then. Most Spanish prisoners had been put ashore swiftly, but Montseny was chaplain to an admiral and he had accompanied his master to the damp country house in Hampshire where he had watched the rain fall and the snow cover the pastures, and where he had learned to hate.

And he had also learned patience. He was being patient now. His hat and cloak were soaked through and he was cold, but he did not stir. He just waited. He had a pistol in his belt, but he reckoned the priming powder would be sodden. It did not matter. He had a knife. He touched the hilt, leaned on the wall, saw another wave break at the street’s end, saw the spray dash past the dim light from an unshuttered window, and then heard the footsteps.

A man came running from the Calle Compania. Father Montseny waited, just a dark shadow in dark shadows, and saw the man go to the door opposite. It was unlocked. The man went through and the priest followed fast, pushing the door open as the man tried to close it. “Gracias,” Father Montseny said.

They were in an arched tunnel that led to the courtyard. A lantern flickered from an alcove and the man, seeing that Montseny was a priest, looked relieved. “You live here, Father?” he asked.

“Last rites,” Father Montseny said, shaking water off his cassock.

“Ah, that poor woman upstairs,” the man made the sign of the cross. “It’s a dirty night,” he said.

“We’ve had worse, my son, and this will pass.”

“True,” the man said. He went into the courtyard and climbed the stairs to the first-floor balcony. “You’re Catalonian, Father?”

“How did you know?”

“Your accent, Father.” The man took out his key and unlocked his front door and the priest appeared to edge past him toward the steps climbing to the second floor.

The man opened his door, then pitched forward as Father Montseny suddenly turned and gave him a push. The man sprawled on the floor. He had a knife and tried to draw it, but the priest kicked him hard under the chin. Then the front door swung shut and they were in the dark. Father Montseny knelt on the fallen man’s chest and put his own knife at his victim’s throat. “Say nothing, my son,” he ordered. He felt under the trapped man’s wet cloak and found the knife, which he drew and tossed up the passageway. “You will speak,” he said, “only when I ask you questions. Your name is Gonzalo Jurado?”

“Yes.” Jurado’s voice was scarce above a breath.

“Do you have the whore’s letters?”

“No,” Jurado said, then squealed because Father Montseny’s knife had cut through his skin to touch his jawbone.

“You will be hurt if you lie,” the priest said. “Do you have the letters?”

“I have them, yes!”

“Then show them to me.”

Father Montseny let Jurado rise. He stayed close as Jurado went into a room that overlooked the street where the priest had waited. Steel struck flint and a candle was lit. Jurado could see his assailant more clearly now and thought Montseny must be a soldier in disguise because his face did not have the look of a priest. It was a dark, lantern-jawed face without pity. “The letters are for sale,” Jurado said, then gasped because Father Montseny had hit him in the belly.

“I said you will speak only when I question you,” the priest said. “Show me the letters.”

The room was small, but very comfortable. It was evident that Gonzalo Jurado liked his luxuries. Two couches faced an empty fireplace above which a gilt-framed mirror hung. There were rugs on the floor. Three paintings hung on the wall opposite the window, all showing naked women. A bureau stood under the window that looked onto the street and the frightened man unlocked one of its drawers and took out a bundle of letters tied with black string. He put them on the bureau and stepped back.

Father Montseny cut the string and spread the letters on the bureau’s leather top. “Is this all of them?”

“All fifteen,” Jurado said.

“And the whore?” Father Montseny asked. “She has some still?”

Jurado hesitated, then saw the knife blade reflect candlelight. “She has six.”

“She kept them?”

“Yes, señor.”

“Why?”

Jurado shrugged. “Fifteen are enough? Maybe she can sell the others later? Perhaps she is still fond of the man? Who knows? Who understands women? But…” He had been about to ask a question, then feared being hit for speaking out of turn.

“Go on,” Father Montseny said, picking out a letter at random.

“How do you know about the letters? I told no one except the English.”

“Your whore made confession,” Father Montseny said.

“Caterina! She went to confession?”

“Once a year, she told me,” Father Montseny said, scanning the letter, “always on her patron saint’s name day. She came to the cathedral, told God about her many sins, and I granted her absolution on his behalf. How much do you want for the letters?”

“English guineas,” Jurado said, “fifteen letters, twenty guineas each.” He was feeling more confident now. He kept a loaded pistol in the bureau’s bottom drawer. He tested the mainspring every day and changed the powder at least once a month. And his fear had subsided now that he understood Montseny really was a priest. A frightening priest, to be sure, but still a man of God. “If you prefer to pay Spanish money, Father,” he went on, “then the letters are yours for thirteen hundred dollars.”