When single mother and Phoenix bartender Kim Ancona is found brutally stabbed to death, her passing tears her family apart. Combing the crime scene, police find an intriguing clue: bite marks on Kim’s body that suggest her attacker has crooked teeth. Detectives turn to Ray Krone, a local mailman with a damaged jaw. A renowned prosecutor pushes for a death sentence, but Ray’s family and appeals attorney refuse to give up hope. They win Ray another trial, forcing him to go up against the same bite mark science that put him away the first time. Ultimately, Ray’s freedom depends on the emerging science of DNA — and finding Kim’s true killer.