“We’ve been through this many times before, Gabriel—the Millennium, the Jubilee, nearly every Christmas and Easter. Sometimes the warnings are delivered to us by the Italian security services, and sometimes they come from our friends in the Central Intelligence Agency. Each time, we respond by clamping down on security, until the threat is deemed to have subsided. Thus far, nothing has materialized. The Basilica is still standing. And so, too, I’m pleased to say, is the Holy Father.”

“Just because they haven’t succeeded doesn’t mean they aren’t trying, Luigi. The Wahhabi-inspired terrorists of al-Qaeda and its affiliates regard everyone who doesn’t adhere to its brand of Islam as kafur and mushrikun, worthy only of death. Kafur are infidels, and mushrikun are polytheists. They regard even Sunni and Shiite Muslims as mushrikun, but to their way of thinking, there’s no bigger symbol of polytheism than the Vatican and the Holy Father.”

“I understand all that, but as you say at your Passover seder, why is this night different from all other nights?”

“You’re asking me why you should take this threat seriously?”

“Precisely.”

“Because of the messenger,” Gabriel said. “The man on whose computer we found these photographs.”

“Who is he?”

“I’m afraid I can’t tell you that.”

Donati turned slowly away from the window and regarded Gabriel imperiously. “I’ve laid bare some of the darkest secrets of the Roman Catholic Church to you. The least you can do in return is tell me where you got the photographs.”

Gabriel hesitated. “Are you familiar with the name Ali Massoudi?’

“Professor Ali Massoudi?” Donati’s expression darkened. “Wasn’t he killed in London a couple of nights ago?”

“He wasn’t killed,” Gabriel said. “He died in an accident.”

“Dear God, please tell me you didn’t push him in front of that truck, Gabriel.”

“Save your sorrow for someone worthy of it. We know Massoudi was a terrorist recruiter. And based on what we found on his laptop, he might have been a planner as well.”

“Too bad he’s dead. We could have put him on the rack and tortured him until he told us what we wanted to hear.” Donati looked down at his hands. “Forgive my sarcastic tone, Gabriel, but I’m not a great supporter of this war on terror we’re engaged in. Nor for that matter is the Holy Father.”

Donati looked out the window once again, at the walls of the Old City. “Ironic, isn’t it? My first visit to this holy city of yours, and this is the reason for it.”

“You’ve really never been?”

Donati slowly shook his head.

“Care to have a look at where it all started?”

Donati smiled. “Actually, I’d like nothing better.”