Scientology Leader David Miscavige Threatens Dad On New Tell-All Book; 5 Explosive Details From 'Ruthless'

Scientology leader David Miscavige has enlisted his lawyers' help against his father, Ronald Miscavige. The latter has written a tell-all book, "Ruthless: Scientology, My Son David Miscavige and Me" and the scientologist wants the court to block its release. Below are five explosive details about "Ruthless," which hits store shelves May 3:

1. David Miscavige's Dad Brought Him To Scientology

As a young asthmatic boy in the 1960s, who would often be bullied, David Miscavige sought solace from Scientology. He mastered many of the teachings faster than any other prodigy and was allowed to facilitate "auditing sessions," also known as counseling, at age 12, per People.

"He advanced very rapidly in the Church," David Miscavige's dad said. He took over as leader when L. Ron Hubbard, the founder of Scientology, died in 1986. After 41 years, Ronald left the group in 2012, per Daily Mail.

Leah Remini says she encouraged David Miscavige's father to write a Scientology book: https://t.co/3Go8B2JAOU pic.twitter.com/FEYx5oY4Cb

— E! News (@enews) April 28, 2016

2. David Miscavige Fought With Tom Cruise

Tom Cruise, the most famous Scientology member, fought with David Miscavige in the beginning. This happened when the group was preparing to welcome the Hollywood actor into the fold.

However, Cruise came late and didn't have dinner at his own welcoming party, News Corp Australia reports. The two would eventually sort it out and become close like brothers.

3. David Miscavige Treated His Staff Badly

While Ronald contends his son was not always ruthless in his youth, he became abusive to his staff as a church leader. He created a punishment room at the Scientology headquarters in California and the staff are not allowed to leave easily the premises.

While he keeps a lavish lifestyle, the rest, including loyal church members, are poor. Radar Online reports that no charges in relation to abuse has been lodged against the Scientology leader.

4. David Miscavige Had His Father Tailed By An Investigator

David hired Dwayne Powell, a former police, to watch Ronald after he left the fold for fear that he would reveal about the activities of the church to the public. If there was anything suspicious in Ronald's behavior, he would be brought to the Scientology headquarters for intervention.

Ron Miscavige claims the Church of Scientology hired private investigators to spy on him: https://t.co/nYsabSSSEE #abc2020 — 20/20 (@ABC2020) April 28, 2016

5. David Miscavige's Lawyers Claim Ronald Had No Meaningful Relationship With His Son

Lawyers sent Silvertail Books, the publisher of "Ruthless," a letter on April 25. "It is clear that the publication of this book has been motivated against the background of an extremely difficult and an unfortunate family history," the lawyers' letter stated, per Tony Ortega, a Scientologist observer.

Ronald admits to domestic abuse when his son was younger, but he explains himself in this video below. The full interview will be shown on "20/20" this Friday, April 29: