A self-help guru whose influence extended to a number of Hollywood celebrities has been found guilty on all charges in his sex trafficking case. The AP reports that Keith Raniere was found guilty in a New York court of manipulating his female devotees — a group that included heiresses and Hollywood actresses — into what prosecutors described as sex slaves.

Raniere’s sentencing is set for Sept. 25. He reportedly plans to appeal his conviction.

“Raniere, 58, once had an international following with a foothold in Hollywood with his self-help group, called NXIVM,” the AP reports. “His adherents included TV actress Allison Mack, best known for her role as a friend of a young Superman in the series ‘Smallville’; a Seagram’s liquor fortune heiress, Clare Bronfman; and a daughter of TV actress Catherine Oxenberg of ‘Dynasty’ fame.”

Brooklyn U.S. Attorney Richard Donoghue said outside court, “Raniere was truly a modern-day Svengali.” He called Raniere a lying manipulator who “ruined marriages, careers, fortunes and lives.”

The report adds: “Among the more damning allegations against Raniere were that he had some women branded with his initials and that he started having sex with a follower when she was 15. Prosecutors said he took a series of nude photos of the teen that were shown at trial, one by one, to the eight women and four men who comprised the jury.”