62-year-old architect, father and former husband Rex Heuermann pleaded guilty to a series of murders that plagued Long Island for 2 decades. As victims’ families gathered in court, Heuermann detailed how he strangled and dismembered the women while hiding in plan sight, posing as a normal suburban Dad. As part of his plea deal, the Gilgo Beach serial killer will be interviewed by the FBI’s Behavioral Analysis Unit to try and understand what drove him to become the monster he is today.