Oh no! Are John Travolta and Tom Cruise's secrets revealed? On March 29, a documentary about Scientology was shown on HBO. The catch? It will be an explosive exposé on the secrets behind the mysterious celebrity religion followed by actors Travolta and Cruise.

Veteran actors John Travolta and Tom Cruise are just two of the famous celebrities who followed Scientology for years. As previously reported, 61-year-old Travolta was instrumental in the "Mission Impossible" actor's conversion to the enigmatic faith. In the controversial HBO documentary titled, "Going Clear: Scientology and the Prison of Belief," it featured Travolta and his journey as a Scientology believer.

Directed by Alex Gibney, "Going Clear" is based on Lawrence Wright's 2013 book of the same title. According to the Daily Mail, the exposé included interviews with former senior members and officials who shockingly exposed the punishments endured by members and how followers were manipulated.

Former member Sylvia "Spanky" Taylor also revealed descriptions of an alleged "prison camp," where people are forced to do 30 hours of hard labor, broken up by three hour rest breaks. She also said she was sent to the camp known as the Rehabilitation Project Force, which is where members are "reindoctrinated."

In addition, News.com.au reported "Going Clear" also included several horrific and fascinating claims about how leader David Miscavige relied on celebs like Tom Cruise and John Travolta to recruit and raise money.

Furthermore, the documentary allegedly claimed that celebrity ambassadors John Travolta and Tom Cruise can't leave the religious organization, which is worth billions, as per the Washington Post. The reason - they are being "blackmailed." A "black PR package" on Travolta and 52-year-old Cruise, which contained all the disclosures they made during auditing sessions that the actors requested not to be recorded but were captured by spy cameras were also featured in the documentary.

Meanwhile, "Grease" star John Travolta finally spoke and defended the Church of Scientology a week after the controversial documentary was aired on HBO, the Huffington Post cited.

"I haven't experienced anything that the hearsay has [claimed], so why would I communicate something that wasn't true for me?" Travolta told the Tampa Bay Times. "It wouldn't make sense, nor would it for Tom [Cruise], I imagine."

"I've been so happy with my [Scientology] experience in the last 40 years that I really don't have anything to say that would shed light on [a documentary] so decidedly negative," he added. "I've been brought through storms that were insurmountable, and [Scientology has] been so beautiful for me, that I can't even imagine attacking it."

The "Hairspray" actor also said he hasn't watched the film and has no plan to, E! News reported.

"Why would I even approach a negative perspective? That would be a crime to me, personally, to do that."

While John Travolta and Tom Cruise seemed to be Scientology's ever-so-loyal followers, Wright and Gibney criticized the actors' silence regarding the alleged abuse claims.

"By now there is a well-documented record of abuses in the Church of Scientology, yet Cruise and Travolta have never spoken out about them," Gibney told Variety in January. "By not speaking out, it's a kind of an endorsement and I think that's why we're right and properly critical."

John Travolta and Tom Cruise, who have remain Scientologists after decades with the religion, have repeatedly denied or ignored accusations of physical abuse and stories of demeaning and mistreatment within the church, Us Weekly said. Meanwhile, the Church of Scientology reps have publicly taken issue with "Going Clear" and released a statement regarding the claims.