The Pope is dead. Behind locked doors of the Sistine chapel, 118 cardinals from around the world will cast their votes in the world's most secretive election. They are holy men, but they are men of the world, and they have rivals. And over the next seventy-two hours one of them will become the most powerful spiritual figure on earth.

In the Eternal City, the most powerful and secretive church on Earth is about to elect a new pope. When a shocking discovery is made deep within the city's ancient catacombs, the Vatican is determined that it must never be made public for the sake of all mankind. But there are others who want to conceal the truth for more sinister reasons.

When the body of a woman is found beneath Michelangelo's dome, Gabriel Allon is summoned by Monsignor Luigi Donati to secretly investigate this mysterious death that has been ruled a suicide--a case that brings about an unthinkable act of sabotage that will plunge the world into a conflict of apocalyptic proportions.

"Lieutenant Billy Boyle could have used a rest after his last case, but when his girlfriend, Diana Seaton, a British spy, goes missing in the Vatican, where she was working undercover, he insists on being assigned to a murder investigation there so he can try to help her. An American monsignor is found murdered at the foot of Death's Door, one of the five entrances to Saint Peter's Basilica. Wild Bill Donovan, head of the OSS, wants the killing investigated....