How did a bizarre confession derail the investigation into the first murder committed by Keith Hunter Jesperson, the notorious “Happy Face Killer,” and allow him to remain on the loose, killing at least seven more women? A new two-hour “20/20” reports on how after authorities discovered the body of Taunja Bennett in the Columbia Gorge in 1990, 57-year-old Laverne Pavlinac confessed to the police that she took part in the crime. She provided convincing evidence that implicated her and her boyfriend, 39-year-old John Sosnovske, in the murder, and they were convicted and sentenced to life in prison. In a shocking twist, Pavlinac’s confession turned out to be false in an attempt to escape what she described as an abusive relationship with Sosnovske. With reporting by “Nightline” co-anchor Juju Chang, “20/20” dives into how Pavlinac was able to dupe police, featuring audio from the couple’s confessions and police interviews, and from the hidden microphone installed in Pavlinac’s apartment when she tried to convince Sosnovske that he was involved in the murder. The two-hour program features an exclusive interview with Melissa Gavin, a friend of Julie Winningham, the last person Jesperson killed before his arrest; and new interviews with John Ingram, lead detective who investigated Bennett’s murder; Jim McIntyre, prosecutor for Pavlinac and Sosnovske’s cases; Darlene Carpenter and Bonnie McAlpine, Pavlinac’s daughters; Michelle White, Bennett’s sister; Melissa Moore, Jesperson’s daughter; and Alafair Burke, bestselling author and former prosecutor who based her first novel on the case. The program also features Chang’s interview with Jesperson from the ABC News archives and gives an inside look at how police ultimately tracked Jesperson down. Learn more about your ad choices. Visit megaphone.fm/adchoices