A deeper dive into the one-and-done-killer phenomenon reveals the horrifying story of a man who pulled off a sophisticated rape-murder against a young couple, then somehow kept a clean profile for three decades, with no one suspecting a thing.   To follow the Unraveled investigations even further, stream the specials exclusively on discovery+. Go to discoveryplus.com/unraveled to start your 7-day free trial today. Terms apply. See acast.com/privacy for privacy and opt-out information.