"What did he say?" asked Quart.

She took an age to turn to the priest, as if she didn't recognise him at first. "Nothing," she replied in a flat voice. "He says he killed him, and that's all."

"And you don't believe him?"

From somewhere in the building came the muffled sound of doors opening and closing. Gris Marsala looked at Quart, infinite contempt in her blue eyes.

After the lawyer and the nun left by taxi, Navajo seemed to relax. "I hate those guys," he confided to Quart. "With all their habeas corpus tricks. I can't stand them, Father, and this one of yours has more tricks up his sleeve than a magician." Once Navajo had got this off his chest, he ran an eye over the papers his colleague had handed to him and then passed them to the priest. "Here's a copy of the statement. This is slightly irregular, so please don't tell anyone. But you and I…" Navajo smiled. "Well. I wish I could have been more help in all this."

Quart looked at him gratefully. "You have helped."

"I don't mean that. I mean a priest arrested for murder…" Navajo fiddled with his ponytail, embarrassed. "You understand. It doesn't make one feel very proud of one's job."

Quart glanced over the photocopied sheets, all written in officialese. Don Priamo Ferro Ordas, from Tormos in the province of Huesca, appears in Seville on such-and-such a date. At the bottom of the last sheet was the priest's signature, a clumsy scrawl. "Tell me how he did it," said Quart.

Navajo pointed at the papers. "Everything he told us is there. And we've guessed the rest from the questions he refused to answer. Bonafe was in the church around eight or eight thirty. He probably came in through the vestry door. Father Ferro went into the church to make his rounds before locking up, and there was Bonafe."

"He was trying to blackmail everybody," said Quart.

"Maybe that was it. Whether Bonafe had an appointment or it was just chance, the parish priest says he killed him, and that's that. He gave no details, only said that afterwards he locked the vestry door, leaving Bonafe inside."

"Inside the confessional?"

Navajo shook his head. "He won't say. But my people pieced together what happened. Bonafe must have been up on the scaffolding in front of the high altar, by the carving of the Virgin. Father Ferro must have gone up there too." Navajo accompanied his account with the usual hand motions. "They argued, struggled, or something. Bonafe fell, or was pushed, from five metres up. He got the wound to his hand when he tried to grab the scaffolding. On the ground, badly hurt but still alive, he dragged himself a few metres and got as far as the confessional. He collapsed inside and died."

The fingers representing Bonafe now lay motionless, on the palm of the other hand, which was the confessional. Quart could picture the scene easily, but the story didn't make sense. He said that to Navajo.

The deputy superintendent returned Quart's gaze without blinking. "I don't agree," he said at last. "As a priest, you would like there to be another explanation. The moral aspect is distasteful to you, I can understand that. But look at it from my point of view." He removed his glasses and held them up to the light. "I'm a policeman, and I have very few doubts: I have a forensic report and a man, even if he's a priest, in full possession of his mental faculties, who confesses to the murder. As we say here: if it's white and in a bottle, it's got to be milk. Skimmed or full cream, however you like it, but it's still milk."

"Fine. You know he did it. But I need to know how and why."

"Well, Father, that's your business. But maybe I can give you a few more details. Bonafe was up on the scaffolding when Father Ferro came upon him." He put on his glasses and took a little plastic bag from his pocket. "Well, look what we found on the corpse."

"It looks like a pearl."

"It is a pearl," said Navajo. "One of the twenty set into the Virgin's face, crown and mantle. And it was in Bonafe's jacket pocket." Quart stared at the little plastic bag, at a loss. "And?" "It's a fake. As are the other nineteen."

In his office, surrounded by empty desks, the deputy superintendent gave Quart the remaining information. He poured the priest a coffee and got himself a bottle of beer. It had taken all afternoon and part of the evening for the necessary tests to be completed, but it was definite that somebody had replaced all the pearls on the carving with fakes. Navajo let Quart read the reports and faxes on the matter. His friend, Chief Inspector Feijoo, had worked till late in Madrid trying to trace the pearls. All the clues pointed to Francisco Montegrifo, the Madrid art dealer who had been Father Ferro's contact for the illegal sale of the altarpiece from Cillas ten years earlier. It was Montegrifo who had put Captain Xaloc's pearls on the market. The description matched that of a set of pearls found in the hands of a fence, a Catalan jeweller who was also a police informer. Montegrifo's role couldn't be proved, but there was evidence. The date the informer gave for the transaction coincided with the resumption of renovation work on the church. Builders' merchants contacted by Navajo's men confirmed that the cost of the goods supplied exceeded the parish priest's salary and the contents of the church collection box.

"So we have a motive," concluded Navajo. "Bonafe's on the trail. He turns up at the church and confirms that the pearls are fake. He tries to blackmail Father Ferro, or maybe the old priest doesn't even give him time." The policeman enacted the scene with his hands. "Maybe he catches him in the middle of what he's doing and kills him. He locks the vestry door and spends a couple of hours at the Casa del Postigo, thinking. Then he disappears for a couple of days." Navajo looked at Quart, as if encouraging him to fill the gaps in his account. Disappointed when Quart said nothing, he continued reluctantly, "Father Ferro won't tell us anything about his disappearance. Strange, don't you think? And you haven't helped much in that area, Padre, if you'll allow me to say so." He took another bottle of beer and a ham sandwich from the small refrigerator behind him and started to eat.

"I'd rather say nothing than lie to you," said Quart. "By talking I'd compromise people who have nothing to do with this. Maybe later, when the whole thing's over… But you have my word as a priest: none of it directly affects the case."

Navajo bit into his sandwich, took a swig of beer, and regarded Quart thoughtfully. "A secret from confession, right?" "You could call it that."

Another bite. "I have no choice but to believe you, Padre. Anyway, I've received instructions from my superiors and, I quote, I'm to proceed with the utmost tact in this affair." He smiled, his mouth full. "Although once the case is resolved, on the surface, I intend to look deeper into it, even if only in a personal capacity. I'm a devilishly curious policeman, if you'll permit the expression." For a moment he became serious. "And I don't like people pulling my leg." He screwed his sandwich wrapper into a ball and threw it in the bin. "I haven't forgotten that I owe you." He raised a finger suddenly: he'd just remembered something. "Oh, by the way. A man was just admitted to the Reina Sofia Hospital in a pretty serious condition. He was found under Triana Bridge a little while ago." Navajo peered at Quart closely. "A small-time private investigator. They say he works for Pencho Gavira, Macarena Bruner's husband. Rather a lot of coincidences for one night, don't you think? I assume you know nothing about this either."

Quart held Navajo's gaze. "No."

Navajo picked his teeth with a fingernail. "I thought not," he said. "The guy's a mess: both arms and his jaw broken. It took him half an hour to get out a couple of words. And when he did, all he said was that he'd fallen down the stairs."