Earlier this month, HBO aired Going Clear: Scientology and the Prison of Belief.
The documentary, which skewers its religious subject, has been watched by more than 5.5 million people and is on track to be the premium cable network's second most-watched documentary of the past decade.
This is a problem for the Church of Scientology, which took out a full-page ad in The New York Times, denouncing the film.
And it's also a problem for the celebrities listed above.
All are believed to be dedicated members of this religion, which some would dub a "cult."
Was Tom Cruise really brainwashed into joining? Is Scientology truly responsible the actor's significant other selections?
Why did Leah Remini join and then leave Scientology for the sake of her daughter?
We may never have the answers to many questions surrounding this practice. But we do at least know which actors, actresses and singers hold its beliefs.
Scroll through the photos featured here and then wonder: Should these famous folks be admired for their commitment?
Or committed for what they admire?