Gilgo Beach serial killer told ex-wife he killed women in their home, new series reveals

The convicted Gilgo Beach serial killer who recently pleaded guilty to seven murders confessed to his ex-wife that he had killed multiple women in the basement of their home while she was away, a new documentary reveals.

In a teaser clip released on Tuesday to promote Peacock’s The Gilgo Beach Killer: House of Secrets, Asa Ellerup said her ex-husband, Rex Heuermann, told her he killed eight women without hesitation. That was the case, though he was only formally charged with – and pleaded guilty to – seven.

At an 8 April court hearing in which he pleaded guilty to seven murders during a 17-year spree, Heuermann acknowledged that he murdered one more woman in whose slaying he had not been charged – but he had not elaborated.

Ellerup, who finalized her divorce from Heuermann in March 2025 after 27 years of marriage, said in the teaser clip that she refused to address her ex-husband as Rex during the jail cell meeting where he made that admission.

“So Mr Heuermann, I understand that you are confessing to me on these murders,” she recalled saying. “Can you please tell me how many of these women did you kill?”

Ellerup told her lawyer: “He said he killed eight women.”

“Eight?” he replied. “Who was the eighth? Because he’s charged with seven.”

Ellerup replied: “I didn’t ask.”

She said Heuermann told her she wasn’t at their Massapequa home when the killings took place, which investigators have also maintained. The bodies of the missing women, killed between 1993 and 2010, were mostly found in marshes alongside a stretch of Long Island’s beachfront.

“He said yes – they were killed in his room downstairs,” Ellerup remarks on the clip. “All except one.”

Investigators searching their suburban home later found a soundproof vault-like room, hundreds of guns and detailed plans for the killings.

Heuermann “walked among us playacting as a normal suburban dad when all along he was targeting these women for death,” Suffolk county prosecutor Ray Tierney said after the Manhattan architect confessed to the crimes in court.

“He thought that by killing them, he could silence them forever and get away with murder,” Tierney added. “But he was wrong.”

Ellerup’s comments were made during the final episode of The Gilgo Beach Killer: House of Secrets, a four-part documentary series. The finale is due to begin airing on Peacock on Thursday.

Heuermann’s confession to his former wife came soon before he pleaded guilty to killing Amber Lynn Costello, 27; Megan Waterman, 22; Melissa Barthelemy, 24; and Maureen Brainard-Barnes, 25, known as the “Gilgo Four”.