Under the Pantheon’s great dome, a woman’s body lies on the marble floor, carefully positioned with a gruesome carving on her back. This horrific murder hurtles Rome’s police force into a collision with U.S. agents -- and a secret that has festered for fifteen years, now unraveling in the world’s most enigmatic city. When Detective Nic Costa arrives at the scene, he is unprepared for what he finds, or for the ambush that leaves his only witness vanished into the night. The dead woman was American. Within hours, U.S. agents descend with a take- no-prisoners style and a shocking story to tell: the killer has struck before, in monuments all over the world, leaving the same cryptic message carved onto the bodies of the victims.

But one agent, beautiful, blond Emily Deacon, has yet another story to tell Nic -- about a stunning act of deception that may lead back to the U.S. government, and her own chilling, personal connection to the killer. Now, as the first murder leads to more grisly slayings and a motley crew of veteran Roman cops jousts with the Americans, Nic is pulled into a woman’s harrowing search for the truth -- a search that will take them both into the mind of a madman, into a shocking conspiracy -- and into a dark episode in a nation’s long-forgotten past.