Women claimed they were branded and required to give naked or compromising photos of themselves as part of a bizarre requirement of a secret sisterhood.
A New York Times report has revealed damning allegations against a US-based group called NXIVM which promotes motivation and self-improvement.
According to the report, written by Barry Meiew, five women in the group were allegedly branded with the initials of NXIVM's leader Keith Raniere, and other female members were called slaves.
The report also revealed how women were told to give the recruiter or "master" compromising materials about themselves with warnings it could be released if they talked about the group.
One of the participants, Sarah Edmonson, told the Times she was told she would get a small tattoo as part of the initiation process.
A cauterising device was used to sear a two-inch-square symbol below the hip in a process which took between 20-30 minutes.
The actress said she wept the whole time.
The women claimed they were instructed to say: "Master please brand me, it would be an honour."
Founded by Raniere in 1998, NXIVM offers "programs that provide the philosophical and practical foundation necessary to acquire and build the skills for success, it's website reads.
Based in Albany, New York, with chapters across the country, Canada and Mexico, the controversial group promotes itself as having an ethical understanding.
Around 160,000 have joined the group led by Raniere who is known within its circles as "Vanguard."
According to the Times the group has had a controversial past and several who spoke with the paper revealed their fears about confessions being used against them in case they leave.
Others allege that he had sex with members and urged women in the group to follow "near starvation diets."
Former members have filed complaints about NXIVM, however according to the Times no action has yet been taken.
One expert told broadcaster NewsChannel 13, these types of groups pray on particular people.
"What is happening essentially is that these organisations and these people leverage your lack of an identity, your lack of a self into their own interest," Psychiatrist Dr Anthony Ferraioli said.
It wouldn't be the first time NXIVM has been in the media limelight.
A 2010 Vanity Fair article revealed how two heiresses to the Seagram brand spent around $100 million to "help finance NXIVM and the alleged investment schemes of its leader Keith Raniere."