Everyone knows Tom Cruise, John Travolta, Kelly Preston, and Kirstie Alley are Scientologists.
But Hollywood is full of other big names who follow the teachings of the controversial church.
Leah Remini is a practicing Scientologist. The King of Queens actress gave birth following the strict Scientology guidelines of silence in the delivery room.
Actress Juliette Lewis is also Scientologist. So is actor Jason Lee from My Name is Earl.
But there are other big personalities you may be surprised to learn are practicing Scientologists.
FOX News' Greta Van Susteran is a long time Scientologist. So is her husband, attorney John Coale, who represented Lisa Marie Presley in her divorce. That's right—Elvis' daughter is also a Scientologist.
Danny Masterson from That 70's Show is a Scientologist. So is former Dharma and Greg star Jenna Elfman.
Rick Ross studies controversial groups like Scientology. He says there is an explanation for the lure of Scientology in Hollywood.
"If you're a celebrity in Scientology, you get special treatment. You're catered to," said Ross.
Mad Men's Elisabeth Moss is a Scientologist. So is Anne Archer from Fatal Attraction. In fact, her son, Tommy Davis, is a leading and vocal spokesman for the church
For all the celebrities who are practicing Scientologists, there are many more who have dabbled in it, but say they are not Scientologists.
Jerry Seinfeld says he's not a Scientologist, but he studied it.
"I took a couple courses a number of years ago that I thought were fabulous," said Seinfeld.
Will Smith and his wife, Jada Pinkett-Smith, donated $1.2 million to a school with Scientology ties, but say they are not Scientologists.
And here's a name that will surely surprise you: the late Sonny Bono.
Officially, he was a Catholic. But the Republican congressman reportedly kept close ties with the Church of Scientology until his death in a skiing accident in 1998.