[Martin Bashir] We've already seen how Scientology attracts celebrities.
But what principles and teachings do members practice, and what does the Church say about some of its most confidential scriptures?
The Church says there is no aspect of life that cannot be improved through the application of Scientology principles, some of which are treatments conceived by L. Ron Hubbard. One such process popular with celebrities is called the "Purification Rundown."
Q. What would that involve?
[Amy Scobee] It's a sauna and vitamin program, some exercise to get your heart rate going.
And then you would take high dosages of Niacin.
[Martin Bashir] Scientologists believe it can dislodge toxins and poisons from the body.
[Tom Cruise] Nearly six years later, many rescue workers are still paying a price for their heroic service at the World Trade Center.
[Martin Bashir] Tom Cruise is a strong advocate of this treatment, co-founding the New York Rescue Workers Detoxification Project, seen here in a Scientology video, which uses L. Ron Hubbard's Purification Rundown principles for those exposed to toxic chemicals after the terrorist attacks of 9/11.
[Tom Cruise] Now, when I started this project, it was because I was in a position where I knew I could help.
[Amy Scobee] When I did it the first time, it was one week, and I felt brighter and more alert. My skin was, you know, vibrant, and stuff like that.
[Martin Bashir] But far away from the limelight of celebrities, Amy Scobee says the program can also be used to discipline Church members. She said she was once told to take part in a Purification Rundown that ended up lasting 8 months.
[Amy Scobee] I was at 5,000 milligrams of Niacin for months and months. I don't know what that did to my body. I have no idea.
[Martin Bashir] How did you feel?
[Amy Scobee] I felt really like -- there was grey stuff coming out of my skin, and I didn't know if it was like my insides coming out or what, after that long of being in the sauna, 5 hours a day every day.
[Martin Bashir] Five hours?
[Amy Scobee] Yeah.
[Martin Bashir] And you kept going?
[Amy Scobee] Yeah.
[Martin Bashir] Well, what happened when you did it for eight months?
[Amy Scobee] That was when I decided I didn't want to be in there anymore, to satisfy somebody else's demands on me, to fix me, because of their preconceived ways.
[Martin Bashir] The Church denies Scobee's characterization, and says the program is a religious service --
and to claim it as a kind of perverse punishment --
is gross in the extreme.
