The pulse-pounding story of the first time in history that the FBI Behavioral Unit created a profile to catch a serial killer. On June 25, 1973, a seven-year-old girl went missing from the Montana campground where her family was vacationing. Somebody had slit open the back of her tent and snatched her from under their noses. None of them saw or heard anything. Susie Jaeger had vanished into thin air, plucked by a shadow. The largest manhunt in Montana's history ensued, led by the FBI. As days stretched into weeks, and weeks into months, Special Agent Pete Dunbar attended a workshop at FBI headquarters in Quantico led by two agents who had hatched a radical new idea: What if criminals left a psychological trail that would lead us to them? Patrick Mullany, a trained psychologist, and Howard Teten, a veteran criminologist, had created the Behavioral Science Unit to explore this new voodoo they called "criminal profiling." At Dunbar's request, Mullany and Teten built the FBI's first profile of an unknown subject: the UnSub who had snatched Susie Jaeger and, a few months later, a 19-year-old waitress. They deduced that he was a white twentysomething who'd grown up without a father; an intelligent, local loner who had served in the military. They predicted he would contact Susie's parents on the anniversary of her murder, and when caught would attempt suicide. When David Meirhofer was arrested fifteen months after Susie's abduction, and confessed to four murders, the profile fit him to a T.