(Photo by L. Cohen/WireImage for Manning, Selvage and Lee)

(Photo by L. Cohen/WireImage for Manning, Selvage and Lee)

After the debut of 'Quiet on Set: The Dark Side of Kids TV,' a documentary series shedding light on reported instances of misconduct during the production of certain Nickelodeon television programs in the 1990s and early 2000s, troubling details continue to emerge from former child actors.

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Segments one and two of the multipart documentary, broadcasted on Investigation Discovery (ID) on Sunday, delved into the significant impact of Nickelodeon producer Dan Schneider on the network's evolution. It explores his role in developing shows and propelling the careers of actors who later rose to prominence, such as Amanda Bynes and Drake Bell, according to TODAY.com.

Within the episodes, certain writers and former child actors from Nickelodeon assert that Schneider, 58, alongside other senior staff members, fostered a backstage environment characterized as toxic, dysfunctional, and abusive. The series presents accusations and personal accounts from cast members of shows including 'All That,' 'Drake & Josh,' 'iCarly,' and others.

A video excerpt from the documentary series, posted on TikTok by the Daily Mail, reveals a troubling accusation, linking Nickelodeon dialogue coach Brian Peck with notorious Chicago serial killer John Wayne Gacy.

@dailymail Former All That star Kyle Sullivan revealed the dark, unsettling discovery he made in the home of Nickelodeon dialogue coach Brian Peck's home. The revelations surfaced in the upcoming docuseries Quiet on Set: The Dark Side of Kids TV, which premieres on ID on March 17. #brianpeck #nickelodeon #quietonset #drakebell ♬ original sound - Daily Mail

Former 'All That' star Kyle Sullivan reminisced, "I remember, at the time, I think it was about two-and-a-half years in, everyone went to Brian's house for a barbecue. And his house was a little off."

During a barbecue gathering at Peck's residence, Sullivan, now 35, said he noticed peculiarities in the house, including vintage toys, comic books, and a garage transformed into what seemed like a "Planet of the Apes shrine."

One painting in particular that caught Sullivan's attention was a depiction of a birthday clown holding balloons, unrelated to the 'Planet of the Apes' theme. Upon inquiry, Peck reportedly disclosed that the artwork was a personal gift from notorious serial killer John Wayne Gacy, known as the 'Killer Clown,' who had murdered numerous individuals in the 1970s.

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Photo by Frank Micelotta/ImageDirect.
(Photo by Frank Micelotta/ImageDirect)

Peck reportedly showcased the painting to other attendees, revealing that he and Gacy were pen pals, even keeping a collection of Gacy's letters and photos in his nightstand. Sullivan expressed discomfort at the situation, describing it as a failure of group psychology.

Sullivan and his fellow 'All That' cast members later discovered that Peck faced allegations of 11 counts of sexually abusing a minor, leading to a 16-month prison sentence.

Additionally, the documentary discloses that Drake Bell, known for his role in the Nickelodeon series 'Drake & Josh,' was the unnamed victim in a 2004 case involving Peck.