You may remember Allison Mack from the early noughties Superman series Smallville. She played Clark Kent’s smart and quirky best friend, Chloe Sullivan.
More recently though, Mack played a prominent role in the cult NXIVM (pronounced “nexium”), and it was her role in this organisation which ultimately saw her arrested on Friday afternoon.
“As alleged in the indictment, Allison Mack recruited women to join what was purported to be a female mentorship group that was, in fact, created and led by Keith Raniere,” United States Attorney Richard P. Donoghue said in a statement.
“The victims were then exploited, both sexually and for their labour, to the defendants’ benefit.”
So, how did a rising young actress end up turning her back on Hollywood only to then become one of the masterminds behind a sex cult?
Well, according to a report by the New York Post, Mack was introduced to the group by her Smallville co-star, Kristin Kreuk.
“Kreuk had come first, sometime around late 2005, early 2006,” said Frank Parlato, the group’s former publicist, who broke the story in June last year.
“Kreuk brought in Allison [soon afterward].”
The young women had initially signed up for what was supposed to be a self-help seminar run by Raniere, 57, before becoming fully-fledged card-carrying members of the cult.
On the back of allegations Raniere was using underage girls for sex, Kreuk, 35, distanced herself from the organisation in 2012.
She released a statement in March saying she is both “horrified and disgusted by what has come out” about the group recently.
“I left about five years ago and had minimal contact with those who were still involved,” she wrote in a statement on Twitter, as reported by Us Weekly.
“I am deeply disturbed and embarrassed to have been associated with NXIVM. I hope that the investigation leads to justice for all those affected.”
But Mack stayed on, and eventually rose through the ranks to become second-in-charge.
It was even Mack who apparently came up with the idea of branding the cult's followers with hers and Raniere's initials.
According to The New York Times, women were instructed to undress and lie on a massage table. They would then have their legs and shoulders restrained.
After saying: "Master, please brand me, it would be an honour," a female doctor would sear a two-inch square symbol featuring the initials onto the skin just below their hip.
The painful procedure took between 20 to 30 minutes to complete.
"For hours, muffled screams and the smell of burning tissue filled the room," wrote The New York Times.
According to Parlato, Mack is now one of the most depraved members of the organisation.
"She started as a slave and she became a slave master," Parlato told The New York Post.
"Her nickname among defectors is 'Pimp Mack.'"
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After the cult came under police investigation last year, both Mack and Raniere knew their days were numbered, and insiders say Mack had been anticipating her arrest.
In a story published by Mamamia back in October, Raniere would manipulate women into having sex with him by claiming it was a "spiritual experience, a transfer of his godlike energy".
Women would also be forced to starve themselves, as this was the body type Raniere found most attractive. Failure to fast would result in "physical punishment".
A physician who was working with the group filed a complaint to the New York State Department of Health in July last year, which ultimately kick-started the investigation.
If convicted of all of her charges, Mack faces a minimum of 15 years in prison, according to People.