The rape and murder of a small-town schoolteacher has the look of a serial predator on the loose. But when forensics and profilers can't identify the attacker, it takes 26 years before a new scientific process offers an unbelievable answer.    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.