John Wayne Gacy shocked the world with is violent and terrifying crimes. The serial killer operated in the Chicago suburbs and killed at least 33 people. “John Wayne Gacy: Devil in Disguise” digs deep into the story that true crime enthusiasts think they know.

Peacock is releasing a new true-crime docuseries “John Wayne Gacy: Devil in Disguise.”

NBC News Studios is bringing a new true-crime docuseries to the streaming world with “John Wayne Gacy: Devil in Disguise.” The documentary promises to take even those who know the story of John Wayne Gacy through parts of the case and serial killer that few know.

The docuseries relies on interviews from law enforcement, neighbors, victims, and family members affected by the murders. Retired Detective Rafael Tovar and Executive Producer Alexa Danner spoke with mitú about working the the case and creating the docuseries.

Tovar was the first Spanish-speaking police officer in the Chicago suburbs in 1970. Eight years later, Tovar was helping to unravel the horrific murders committed by John Wayne Gacy.

“It was a phase into the case because when we first started, we were working on a missing person report for one person, never figuring that it was going to turn out to be what it turned out to be,” Tovar recalls about the case. “It was something new every day until we started digging that’s when everything broke loose, and it became the case of a lifetime for a police officer.”

The former Des Plaines detective remembers the moment that case was going to be much more than anticipated. Around December 21, when the officers executed a second warrant on John Wayne Gacy’s suburban home, Tovar and other authorities made gruesome discoveries. Tovar remembers digging under the house with an evidence technician when they discover three left femurs. The bones were too decayed to belong to the last victim, Robert Piest.

“The John Wayne Gacy story has certainly been told multiple times over the year and I think that there is a sense that there’s a narrative out there that is known and accepted,” Alexa Danner, an executive producer on the docuseries says. “What we really found as we began to produce this documentary was that there are a lot of questions that remain about the case. There’s a lot of mystery still surrounding it.”

Danner promises that even those who think they know the John Wayne Gacy story well will learn new things about the crimes. “John Wayne Gacy: Devil in Disguise” talks to people never interviewed before and takes a hard look at the case like never before.

The investigation into John Wayne Gacy changed law enforcement practices drastically. Procedures were adjusted to better assist with missing persons reports, especially children. Tovar also shared that John Wayne Gacy himself claimed to have had other victims.

“I was transferring him from our police lockup to the county lockup. Just in conversation, I asked him, ‘John. There are a lot of numbers going around. How many people did you kill?’ and he said, ‘Well, I’ve said this, I’ve said that, but 45 sounds like a good number.’ So I asked him, ‘Well, where are they?’ He said, ‘No. That’s your job to find out,’” Tovar recalls about that conversation. “He was the type of guy that knew that you knew something or that you were going to find out, he’d be totally honest with you. If he didn’t think that you were going to find out, he liked to play mind games with you. I believe him. Everything else he told me was true, so I believe that there are more out there.”

The show will take people through Gacy’s life before the violent attacks he became known for after his arrest. It will show people the life he had in Iowa that might have been a warning sign of things to come. The docuseries explores lingering questions about his mother’s ignorance about her son’s dealings and questions about the real body count.

Danner recalls a psychiatric report done on Gacy after his arrest that should have given everyone pause.

“It essentially said that this man would not stop behaving like this. There’s no known way to stop his behavior or change it,” Danner says. “To look back ten years before he’s arrested for all of these killing and know that he was already being assessed that way or diagnosed that way is really troubling and horrible.”

“John Wayne Gacy: Devil in Disguise” will be available for streaming March 25 on Peacock.

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