Lt. William Somerset, a burnt-out veteran cop, is on the brink of retirement. Forced to train his ambitious and eager replacement, Somerset is teamed with Detective David Mills on an investigation that draws these disparate cops deeper and deeper into the twisted world of a cunning and meticulous criminal. He is methodical, exacting and grotesquely creative. He is known as John Doe and he is the most vicious serial killer alive, fashioning murders based on the seven deadly sins. As each new victim is discovered, the detectives must combine their collective experiences to track the trail of a killer bent on seeking attrition for society's sins.