Long Island serial killer Rex Heuermann confessed to murdering seven women in the home he shared with his ex-wife, Asa Ellerup, according to a preview for Peacock’s “The Gilgo Beach Killer: House of Secrets.” Heuemann pleaded guilty to seven murders and admitted for the first time to an eighth. Ellerups stated that Heuernn looked nervous before confessing to the murders and did not kill any of his victims while she was home. As part of his plea deal, He will work with the Federal Bureau of Investigation's Behavioral Analysis Unit to analyze offender's motivation, victim selection, sophistication level, and the sequence of events.