In the fall of 1977, the bodies of young women begin piling up in Los Angeles. Almost all were nude, showing signs of torture, and discarded on hillsides. Overnight, the city became gripped with terror as the press dubbed the perpetrator "The Hillside Strangler." As the killings escalated, police received reports that two suspicious men were spotted flashing police badges and asking women to pull over. Suddenly, detectives realized that they were facing not a single serial killer but a pair working in tandem. Even more terrifying: the perpetrators may be members of law enforcement. A large task force was formed, but every lead went nowhere. Then, in late February 1978, after ten women had been slaughtered, the killings inexplicably stopped. Nearly another year passed before two murders more than 1,200 miles away opened the door to a bizarre family saga that ultimately uncovered the identity of the Hillside Stranglers.

It was just a normal night for 18-year-old Samantha Koenig. She was closing the coffee kiosk where she worked in Anchorage, Alaska—like she had done many times before—when one last customer came in: a man known in the community as a local business owner and caring father. But lurking beneath that anodyne surface was a rapist and a ruthless killer with a penchant for selecting random victims throughout the country. Israel Keyes' kidnapping of Koenig led to an intense manhunt and a cross country investigation that ended his reign of terror. While in custody, Keyes played cat and mouse with detectives, revealing some details about his crimes and his missing victims. In the end, Keyes had one last surprise.