Kids were forced to stare at each other for hours, ask obscure questions to inanimate objects, spend hours sweating out "toxins" in a sauna for "purification" and when a couple of teenagers were busted doing "sexually unethical" things, part of their punishment was wearing black and running, not walking, all the time.
Jenna says she was so "completely brainwashed" that whenever she questioned L Ron Hubbard's bizarre theories, "You think that you're crazy".
"They have these slogans like, 'Think for Yourself' and, 'What is True is True for You' but these things are completely ironic. They're so far from the truth.
"If you don't agree with Scientology doctrine, what L Ron Hubbard says, then they teach you that there's a word that you don't understand. You have to keep finding them and looking them up in the dictionary until you finally understand it and if you don't understand it then they say that it's because you've done bad things."
The Church started as a self-help group in the mid-1950s. Jenna says it lures in followers using "personality tests" to pick on an individual's insecurities. Scientology promises to repair your marriage, help you earn more money, be more successful... And celebrity endorsements (most notably Tom Cruise and John Travolta) back up all the hype.
"When you're first getting in it's completely different. People are ... kissing your butt, showering you with love, saying how great you are," Jenna explains.
"Once you're in, they're like, 'We don't need to keep kissing this person's butt' and it's on to the next person.
"By the time you start seeing holes you've already put in too much money into it, too much time, you've brought your friends in to it, your family and it's too hard to leave."
She says the ultimate belief of Scientologists is that "our spirits are trapped in our bodies and we rely on them and Scientology is the only thing that can bring us back."
Because the body is a just a vessel for the spirit, any sickness or expression of emotion is deemed weak. Poorly people are sent in to isolation, crying is seen as being "needy" and giving birth should be done in silence. Unless you're part of the most dedicated part of the church - Sea Org - where falling pregnant gets you kicked out or encouraged to have an abortion.
"To me, the Church is a dangerous organisation whose beliefs allow it to commit crimes against humanity and violate basic human rights," Jenna writes in her book.
"... Scientology has always been a game of power and control."
Jenna freed herself from Scientology, with her now husband, when she was 21. She first took aim at the Church in 2008. Private investigators were sent to follow her, an intimidate technique intending to pipe Jenna down.
"In the end, I'm just not afraid of them any more," Jenna says today.
"What are they gonna do at this point that they haven't already done?"
Beyond Belief, by Jenna Miscavige Hill, published by Harper Collins, is available now. RRP $29.99. Check out Jenna's website for more infohere.
