HBO has released the first Going Clear trailer for director Alex Gibney’s (Taxi to the Dark Side) buzzworthy documentary chronicling the Church of Scientology. Based on the book of the same name by author Lawrence Wright, the film seeks to expose the truths about Scientology, its inner workings, and why it’s been able to remain so secretive all these years. I caught the film at Sundance and while it covers a lot of ground we’re already familiar with, its biggest value is the bevy of interviews and testimonials with former Scientology members, including a couple of very high ranking former officials.

For a religion so secretive, it’s pretty stunning to hear about its machinations from the people who were on the inside—and even from some of the people that were pulling the strings. It’s a fascinating watch, and I’m sure it’s going to stir up a lot of attention once it’s unveiled to the public.

Watch the first Going Clear trailer below, via HBO Docs. Going Clear: Scientology and the Prison of Belief premieres on HBO Sunday, March 29th at 8pm with an encore the next night. Click here to read Matt’s review from Sundance.

Here’s the official synopsis for Going Clear: Scientology and the Prison of Belief:

Based on the book by Pulitzer Prize winner Lawrence Wright, GOING CLEAR, profiles eight former members of the Church of Scientology, whose most prominent  adherents include A-list Hollywood celebrities, shining a light on how the church cultivates true believers, detailing their experiences and what they are willing to do in the name of religion.