In a promo for her sit-down interview with ABC News' Dan Harris, the former King of Queens star reveals how tough it was to walk away from Scientology. "The decision to leave is you're giving up everything you have worked for your whole life," she said. "I feel that people need to understand this has been my whole life and I want them to understand how it happens."
Remini added, "As time goes on, you start to lose touch with the real world. The mindset becomes us against them."
This way of thinking also applied for one of the church's most famous members. "Being critical of Tom Cruise is being critical of Scientology itself," she claimed in the upcoming 20/20 interview. "You are evil."
Harris responded to Remini's comment by asking, "If you knew Tom Cruise was watching this, what would you say to him?"
The actress' full 20/20 interview, which coincides with the release of her new book, Troublemaker: Surviving Hollywood and Scientology, airs Friday night on ABC.
In a statement to ET, the Church of Scientology said, "It comes as no surprise that someone as self-absorbed as Leah Remini with an insatiable craving for attention would exploit her former faith as a publicity stunt by rewriting her history with it, including omitting that she was participating in a program to remain a Scientologist by her own choice, as she was on the verge of being expelled for her ethical lapses."