In his time investigating crimes for both the Boston cops and General Ike's European forces, Lieutenant Billy Boyle hasn't encountered a serial killer. But now it looks like he may—a serial killer with a particularly frightening agenda.

Two officers from the American troops stationed in Caserta, Italy, not far from Naples, have been found murdered. Lieutenant Norman Landry was found behind a supply tent with his neck snapped. Captain Max Galante, MD, was strangled on the same night, and his body left in a garden outside HQ. The MOs are completely different, and it seems like the officers had no connection to each other, but one frightening fact links the murders: each body was discovered with a single playing card: the Lieutenant, the ten of hearts; the Captain, the jack of hearts. The message seems to be clear—if the murderer isn't apprehended, the higher ranks will be next.

Billy is sent to Italy for the investigation, which grows increasingly sinister. But he has other things on his mind, too. His girlfriend, Diana, is on a very dangerous spy mission, and Billy doesn't know when—or if—he'll see her again. To make matters worse, Billy's just learned that his baby brother, Danny, is being sent over to Europe as an infantry replacement, an incredibly dangerous assignment. And all around him, he sees GIs suffering from combat fatigue preparing for another battle. As the invasion at Anzio begins, Billy needs to keep a cool head amidst fear and terror as the killer calculates his next moves.