When the body of young novice Sister Camille is found garroted in St. Marguerite's cathedral, Detectives Bentz and Montoya are called in. For Montoya, the brutal crime scene is disturbingly familiar - his aunt, also a nun, was murdered. And the connections don't end there. Montoya knew this victim in high school, and even knew the prime suspect, Father Frank O'Toole, with whom Camille was rumored to be having an affair. The deeper the investigation goes, the eerier it gets. More nuns are dying - brutally slaughtered by someone who seems to know their darkest secrets. Bentz is sure Father O'Toole is their man. But there are other suspects, too, including a ruthless murderer believed to have died years ago. Has the monstrous killer known as Father John returned? Or is the truth even more twisted and terrifying?