The voice of alleged Gilgo Beach serial killer Rex A. Heuermann is heard at the end of the first trailer for a new documentary premiering Tuesday on Peacock, hinting at a cameo by the alleged killer as he speaks on the phone from the Suffolk County Jail in Riverhead.

"I’m doing great, now that I have you on the phone," wife Asa Ellerup tells him as he appears to call to check in. She has since gotten a divorce from Heuermann.

"The Gilgo Beach Killer: House of Secrets," a three-part series from executive producer Curtis "50 Cent" Jackson, promises exclusive interviews with Heuermann’s family and friends that will "unravel a chilling portrait of a man accused of living a double life," a news release from the streaming service said Friday. Heuermann’s family was reportedly paid more than $1 million to allow the documentary crew access into their Massapequa Park house and lives.

The nearly two-minute sneak shows Ellerup grappling with the idea that her husband was responsible for the notorious decades-old killings, which features never-before-seen images of the accused killer and his family.

"Does everyone really believe everything they hear?" Ellerup asks in the preview.

Daughter Victoria Heuermann is also shown wrestling with the new public idea of who Suffolk prosecutors say her father is and the man she knew before.

"One person saying this, one person saying that, but my memory says this," she says.

A man who identifies himself as Heuermann’s best friend suggests he confronted the architect about his involvement in the killings.

"Did you do it?" the man asks in the preview.

The trailer also shows footage from inside the family’s Massapequa Park home, childhood photos of Heuermann and images from the couple’s 1996 wedding.

All three one-hour episodes of the documentary will be available to stream Tuesday morning, Peacock announced in a news release. A separate documentary about the case was done with cooperation of some of his victims' families, becoming the most streamed series on Netflix when it premiered March 31.

Heuermann has been incarcerated at the Suffolk County jail in Riverhead since his initial arraignment on July 14, 2023. He is charged with murder in the deaths of Maureen Brainard Barnes, Megan Waterman, Amber Lynn Costello, Melissa Barthelemy, Jessica Taylor and Valerie Mack, whose remains were all found at Gilgo Beach, as well as Sandra Costilla, whose body was discovered more than 65 miles away in the Southampton hamlet of North Sea.

Partial remains of Taylor and Mack were also found in wooded areas north of the Long Island Expressway in Manorville. The killings occurred between November 1993 and September 2010.

Heuermann is due back in court June 17 for a continuation of a suppression hearing regarding DNA evidence in the case. The defense will call its first witness on that date, a courts spokesperson said following his most recent court date in April.