Enlisted by an archaeologist friend to help excavate a top-secret historical site, husband-and-wife team Sam and Remi Fargo discover clues alluding to the hidden tomb and treasure of Attila the Hun and embark on a high-stakes chase through numerous countries, where they are pitted against dangerous adversaries.
The first message sent to Tom Thorne's phone was just a picture - the blurred image of a man's face, but Thorne had seen enough dead bodies to know that the man was no longer alive. But who was he? Who sent the photograph? And why? While the technical experts attempt to trace the sender, Thorne searches the bulletins for a reported death that matches the photograph. Then another picture arrives.