Watch The Trailer For HBO’s Documentary On Scientology

The first trailer for the highly anticipated documentary on Scientology debuted today. Going Clear: Scientology and the Prison of Belief, directed by Alex Gibney, promises an inside look into one of the most controversial religions in the United States. Naturally, the Church of Scientology is quite angry about it. The film made a major impact at Sundance — Salon reports it debuted to a "packed house." Salon also reports the project will include John Travolta, Tom Cruise, and Paul Haggis. Meanwhile, the Church of Scientology has vehemently opposed the documentary. It commissioned a full-page ad in both The New York Times and The Los Angeles Times in the days leading up to its Sundance premiere. These ads claim the documentary is a false depiction of Scientology. Going Clear: Scientology and the Prison of Belief premieres Sunday, March 29 at 8 p.m on HBO. Below, the trailer that's sure to continue to make headlines.