Leah Remini
Former "King of Queens" star Leah Remini turned her back on Scientology in 2013, and now she's spilling secrets about Tom Cruise's beloved church. The actress is pictured above Jan. 14, 2014. Getty Images

Former “King of Queens” actress Leah Remini has been outspoken since she left the Church of Scientology. But for the first time since her departure from the religion in July 2013, Remini gave an exclusive tell-all interview on “20/20.” She shared secrets from within the church and stories about some of its most prominent members, like “Mission Impossible” star Tom Cruise.

To catch Remini’s expected exposé, tune in to ABC Friday at 10 p.m. EDT. The network also says that Cruise’s third ex-wife, Katie Holmes, spoke out about Remini at the end of the special.

Some sensational clips from the interview have already leaked. Remini, who became involved with Scientology when she was 8, said the church gives children extravagant self-worth. “Because Scientologists view children as spiritual beings, you’re not treated as a kid,” the actress, 45, told ABC News ' Dan Harris. “You’re given a lot of responsibility, your ego becomes extremely inflated.”

Her decision to leave after more than 30 years wasn’t easy. But the main thing that made her stray was her daughter. "You are dependent on the church. In 10 years, if I didn't want to be connected to the church anymore, my own daughter would be taught to disconnect from me. I didn't want to create that. I didn't think that would be healthy for her,” she said.

In another part of the interview, Remini revealed she was “written up” after she told Cruise and Holmes, his then-girlfriend, “to get a room” when they got intimate in front of her. "He was like, forcibly kissing Katie," she said. The New York native wasn’t permitted to speak out about Cruise while she was involved with the religion because “being critical of Tom Cruise is being critical of Scientology itself.”

Remini's memoir, “Troublemaker: Surviving Hollywood and Scientology,” will hit bookshelves Tuesday.

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