Unmasking A Killer profiles the terrifying real-life story of the Golden State Killer a man responsible for a staggering 51 attacks and 12 murders in California. Investigators have searched for the sadistic criminal for forty years and with recent evidence suggesting he may still be alive, in 2016 the FBI Sacramento announced a national campaign and $50,000 reward to identify the perpetrator, making the investigation hotter than ever. The series takes an in-depth look at the manhunt, patterns, escape methods and mind games of the Golden State Killer. Interviews with investigators, law enforcement and victims, who have never spoken out publicly, offer information to help solve the mystery of a man who has managed to successfully fly under the radar for decades.