21 Famous Church Of Scientology Members

On Tuesday, HBO revealed it has 160 lawyers preparing for its new documentary on the Church of Scientology.

The documentary is based on Pulitzer Prize-winning author Lawrence Wright's controversial book "Going Clear: Scientology, Hollywood, & the Prison of Belief," which grew out of a New Yorker profile on former Scientologist director Paul Haggis.

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The new HBO documentary "is expected to feature new revelations about the controversial religion and its famous followers Tom Cruise and John Travolta," according to The Hollywood Reporter.

Cruise, Scientology's most prominent member, became involved with the church in 1990 through his first wife, actress Mimi Rogers.

"It's a privilege to call yourself a Scientologist, and it's something that you have to earn,"Cruise said in 2004.

In 2005, he told Matt Lauer on "Today," "It is a religion. Because it's dealing with the spirit — you as a spiritual being. It gives you tools you can use to apply to your life."

By 2013, Cruise admitted that ex-wife Katie Holmes divorced him in part to protect the couple's daughter Suri from Scientology. He also admitted that Suri is no longer a practicing member of the church.

Cruise, however, is still an active member — and he's not the only one. From "Mad Men" to "The Simpsons," see who practices Scientology. 

Actress Kirstie Alley

The former "Cheers" star says the religion helped her overcome a cocaine addiction. 

In 2010, rumors swirled her weight loss program, Organic Liaison, was a front for Scientology, a claim the actress vehemently denied. 

Actress Bijou Phillips

Indie goddess Bijou Phillips, most recently known for her role on "Raising Hope," is daughter of the "Mamas and Papas" singer John Phillips.

Bijou is married to Danny Masterson and the two frequently go to Scientology events together. 

Actor Danny Masterson

Masterson is best-known for his role on "That '70's Show." He defended Tom Cruise for the actor's leaked Scientology video back in 2008. 

In an interview with Paper Magazine in 2009 he explained the religion as follows:

"The definition of Scientology is 'the study of knowledge,'"said Masterson. "Obviously, the more knowledge you have in a given field, such as life, the more confident you are as a person."