Father Oscar took off his glasses and wiped them on his shirt. He squinted warily at Quart. "That's all that matters, isn't it? The church, Father Ferro, me – you don't really care about any of it." He clicked his tongue. "You have your mission." Absently, he cleaned one lens, then the other. "Who Vespers is," he said, "isn't important. The message is a warning. Or an appeal to whatever there is that's still noble in the firm that you and I work for." He put on his glasses. "A reminder that honesty and decency still exist."

Quart made a sour face. "How old are you?" he asked. "Twenty-six? With age you'll find you get over that nonsense."

Father Oscar raised an eyebrow. "Did you acquire your cynicism in Rome," he asked, "or was it something you already had? Don't be foolish. Father Ferro is an honest man."

Quart shook his head. An hour before, he had been at the archbishop's palace leafing through Father Ferro's file. Monsignor Corvo confirmed the main points during a brief conversation with Quart in the Gallery of the Prelates, beneath portraits of their graces Gaspar Borja (1645) and Agustin Spinola (1640). Ten years ago, Father Ferro was the subject of an ecclesiastical inquiry in the diocese of Huesca as a result of an unauthorised sale of church property. Towards the end of his time as parish priest in Cillas de Anse in the Pyrenees, a panel and a figure of Christ on the Cross disappeared. The figure of Christ was nothing special, but the panel dated from the early fourteen-hundreds and was attributed to the Master of Retascon. The local bishop was very concerned when he found out it was missing. The parish was a poor one, and that kind of episode was common at the time, when a parish priest was almost entirely free to dispose as he wished of the heritage entrusted to him. Father Ferro escaped lightly, with only a reprimand from his ordinary.

It certainly bore out what Bonafe had hinted at. Quart sensed that Corvo, uncharacteristically open on this occasion, was probably quite happy that this murky area of Father Ferro's past was becoming public knowledge. Quart suspected even that the journalist's source had been, directly or indirectly, the archbishop himself. In any case, the story about Cillas de Anso was true; Quart got the next instalment at police headquarters, when Navajo made a couple of calls to his colleague in Madrid, Chief Inspector Feijoo, head of investigations into thefts of works of art. An altarpiece by the Master of Retascon, identical to the one that disappeared from Cillas de Anse, was acquired with a receipt in due form by Claymore's Auctioneers in Madrid. Francisco Montegrifo, director of Claymore's and a well-known art dealer, confirmed that a certain sum was paid to the priest Don Priamo Ferro Ordas. A pittance compared to what the picture fetched at auction, but it was a question of supply and demand, Montegrifo pointed out to Chief Inspector Feijoo, who then passed the information on to Navajo.

"As for Father Ferro's honesty," Quart said to Father Oscar, "perhaps he hasn't always been so upright."

"I don't know what you're insinuating," said the the young priest. "And I don't care. I respect the man that I know. Go look for your Judas elsewhere."

"Is that your last word? It may not be too late."

Father Oscar glared at him. "Not too late? Is that a hint that I might yet be pardoned? As long as I co-operate?" Shaking his head in disbelief, he stood up. "It's funny. Yesterday Don Priamo mentioned that he'd had a conversation with you at the duchess's and that maybe now you were beginning to understand. But whether you understand or not is irrelevant. Killing the messenger is what matters, isn't it? To you and your bosses, it's not the fact that there's a problem but that someone has dared to bring the problem into the open."

With a last dismissive look he headed towards the vestry. He stopped suddenly, as if he'd thought of something, and half-turned to Quart.

"Maybe Vespers was wrong after all," he said, his voice echoing in the vault. "Maybe the Holy Father wasn't worthy of his messages."

A shaft of sunlight shifted slowly from left to right across the worn flagstones at the foot of the high altar. Quart looked up at the window through which the light streamed: it depicted the Descent from the Cross. The stained glass from Christ's torso, head, and legs was missing, making it seem as if Saint John and Mary were bringing only two arms down from the Cross. The lead around Christ's missing figure formed a ghostly outline, a blurred presence making the mother's and the disciple's suffering and effort appear futile.

Quart walked to the high altar and the entrance to the crypt. He stopped beside the iron gate at the top of steps descending into darkness and touched the skull carved in the lintel; as before, the stone chilled his hand. Trying to suppress his uneasiness at the silence of the church, the gloomy staircase, and the musty air rising from the crypt, he made himself stand there. From the Greek kryptos, hidden, he whispered. Where stone held the key to other times, other lives. Where the bones of fourteen dukes of El Nuevo Extremo lay, and the shadow of Carlota Bruner.

The patch of sun on the ground had moved a whole flagstone to the right and was shrinking when the IEA agent proceeded to the middle of the nave. He looked up at the gap where the chunk of cornice had come away, fatally injuring the archbishop's secretary. He went over to the scaffolding supporting the cornice and shook it, but it seemed firmly anchored. He stood at the approximate spot where Father Urbizu had stood when he was killed. There was enough room for someone to stand on the scaffolding under the cornice and dislodge a chunk, but the police report discounted the possibility. That, and the account of the municipal architect's fall – this time with witnesses present – seemed to rule out human intervention in both deaths, attributing them, as Vespers and Father Ferro claimed, to the wrath of God. Or to fate, which in Quart's view was a cosmic watchmaker who seemed to wake up every morning with a taste for practical jokes.

Or to the clumsiness of sleepy Rabelaisian gods. When they dropped a slice of their morning toast, it always fell to earth butter side down.

Vespers' motive was clear. His computer messages were an appeal to common sense, an appeal for justice, to vindicate an old priest fighting his last battle in a forgotten corner of the board. But Father Oscar was right when he said that Vespers had made a mistake in sending his messages. Rome couldn't understand them, and Spada had sent the wrong man. The world and the ideas to which the hacker had made his appeal had long ceased to exist.

Quart took a few steps back and examined the scaffolding and damaged windows on the left-hand side of the church. When he turned again to the nave, Gris Marsala was behind him, watching.

The exhibition Religious Art in Baroque Seville was declared open, and applause filled the rooms of the Cartujano Bank Arts Foundation. Afterwards, waiters brought round trays of drinks and canapes while guests admired the works that would be on display in the Arenal building for the next three weeks. Between Christ of the Good Death by Juan dc Mesa, on loan from the university, and a Saint Leandro by Murillo from the cathedral vestry, Pencho Gavira greeted the gentle-mcn and kissed the hands of the ladies, smiling to left and right. He wore an immaculate charcoal-grey suit and the parting in his gelled hair was as perfect as the white collar and cuffs of his shirt. "A very good speech, Mayor."

The banker and Manolo Almanzor, mayor of Seville, exchanged slaps on the back. The mayor was chubby, with a moustache. He had an honest face that had won him the popular vote and a re-election, but a scandal concerning improper contracts, a brother-in-law grown wealthy in dubious circumstances, and accusations of sexual harassment by three of the mayor's secretaries at the town hall all meant that now, less than a month away from the municipal elections, he was certain to lose.