"To sum up," he said, trying to sound slightly less harsh and looking down at his notes to avoid the priest's eyes, "you deny that you wrote the message that was sent to the Holy See. You also deny that you have any idea who sent it or any clues as to the author or his intentions."

"Yes," said Father Ferro.

"Before God?" asked Quart, feeling ashamed of himself – this was going too far.

The old priest turned to Corvo, in an appeal for help that the archbishop could not ignore. Corvo cleared his throat and raised his hand bearing the ring.

"Let's leave the Almighty out of this, shall we?" the prelate said through the smoke from his pipe. 'I don't think we need put anyone on oath in this conversation."

Quart accepted this in silence and turned once more to Father Ferro. "What can you tell me about Oscar Lobato?" he asked.

The old priest shrugged. "Nothing. Just that he's a fine young man and an honourable priest." His unshaven chin trembled slightly. "I'll be sorry to see him go."

"Does your assistant know computers?"

Father Ferro narrowed his eyes. His expression was wary now, like that of a peasant watching storm clouds approach.

"You should ask him." He jerked his chin at the door. "He's out there, waiting for me."

Quart smiled almost imperceptibly. He appeared confident, but there was something about all this that made him feel he was crossing a void. Something out of place, a wrong note. Nearly all that Father Ferro said was true, but there was a lie in it somewhere. Maybe only one, and maybe not a serious one, but a lie.

"What can you tell me about Gris Marsala?"

The old priest's lips tensed. "Sister Marsala has a dispensation from her order." He glanced at the archbishop as if for corroboration. "She's free to come and go as she pleases. Her work is entirely voluntary. Without her, the building would have fallen down by now."