Mack, who costarred on Smallville, faces a minimum of 15 years in prison if convicted of sex trafficking and forced labor charges

The allegations are as elaborate as they are shocking.

Actress Allison Mack, best known for her role as the wholesome Chloe Sullivan on the TV show Smallville, is charged with sex trafficking in connection with a controversial self-help group that one former member described as a “cult.”

In a statement following Mack’s arrest and a letter opposing Mack’s bail, federal prosecutors have revealed disturbing accusations — including coercive sex, restrictive diets and blackmail — about the inner-workings of the organization, called Nxivm.

The group’s co-founder Keith Raniere faces sex trafficking and forced labor charges along with Mack. According to a statement from prosecutors announcing Mack’s Friday arrest, Raniere operated a series of self-help workshops, all under the umbrella of the Albany, New York-based organization founded around 2003.

Prosecutors allege Raniere ran Nxivm like a “pyramid scheme” and created a secret society within the group called “DOS” — which according to prosecutors is “an acronym standing for a Latin phrase that loosely translates to ‘Lord/Master of the Obedient Female Companions.’ ”

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Investigators allege Raniere, who was known as “Vanguard” within the group, occupied the top of the pyramid and was the DOS’ only male member. Beneath him were tiers of female “slaves,” each of whom could become a “master” by recruiting other women into the group, according to prosecutors.

Mack and other women occupied the next tier down from Raniere, authorities believe. According to the letter prosecutors sent to the judge opposing Mack’s bail, the actress “was focused on recruiting attractive young women who could meet Raniere’s sexual preferences.”

In her alleged role in the group, Mack made new recruits provide “collateral” — defined by prosecutors as “highly-damaging information about friends and family members, nude photographs and/or rights to the recruit’s assets.”

Allison Mack
| Credit: Matt Baron/BEI/REX/Shutterstock

The collateral, prosecutors allege, gave Mack leverage with which to blackmail slaves if they told people of DOS’ existence or tried to leave the group.

Prosecutors allege that the women Mack is accused of victimizing, referred to in the statement and indictment as Jane Doe 1 and Jane Doe 2, “believed that if they did not participate in [sexual] activities with Raniere, their collateral would be released.”

Collateral was regularly required of women who joined DOS and it was explained as a tool to ensure that what the participants learned was kept a secret from outsiders, according to a criminal complaint against Raniere.

“In many cases, the masters helped the prospective slaves develop ideas for what would be appropriate collateral or instructed the prospective slaves on lies to tell in order to make the collateral more damaging,” the complaint states.

Accusations of Sleep-Deprivation and ‘Restrictive Diets’

Authorities suspect Mack forced DOS slaves, including Jane Doe 1, to have sex with Raniere and that Mack “groomed DOS slaves for sex with Raniere by requiring [them] to adhere to extremely restrictive diets and not remove their pubic hair (in accordance with Raniere’s sexual preferences) and by requiring them to remain celibate and not to masturbate.”

According to arguments prosecutors made in court documents, Mack allegedly demanded that the group’s slaves partake in “readiness” drills requiring them to respond to their masters at any time of night.

Mack’s slaves were also allegedly “kept seriously sleep-deprived and emaciated to the point where they stopped menstruating.”

Additionally, DOS slaves were allegedly “branded in their pelvic regions with a cauterizing pen with a symbol that, unbeknownst to them, incorporated Raniere’s initials.”

Prosecutors claim that during ceremonies in which her slaves were branded, Mack “placed her hands on the slaves’ chests and told them to ‘feel the pain’ and to ‘think of [their] master,’ as the slaves cried with pain.”

The prosecutor’s letter to the judge in Mack’s case also alleges that she “provided naked photographs of her slaves to Raniere and was aware of Raniere’s proclivity for having sex with multiple young women.”

In return, according to the letter, Mack allegedly “received financial benefits [in] the form of continued status and participation in DOS, as well as financial opportunities from Raniere.”

Keith Raniere

Mack has previously discussed her connection with Raniere. “Over the course of several years, Mr. Raniere mentored Allison in her study of acting and music,” her website stated. (It was taken offline after her arrest.)

For the past two decades, an estimated 16,000 people have paid as much as $3,400 for an executive coaching workshop offered by Nxivm, which promises to take participants on a journey of personal discovery and development, according to previous PEOPLE reports.

Both Mack and Raniere face 15 years in prison, minimum, if convicted.

Mack pleaded not guilty to her charges on Friday. According to court documents obtained by PEOPLE, she is negotiating a possible plea deal.

A representative for Mack has declined to comment to PEOPLE on her arrest. PEOPLE’s calls to her attorney, Sean Stephen Buckley, have not been returned.

Raniere has not yet entered a plea. PEOPLE’s attempts to contact his attorney, Danielle R. Smith, were not immediately returned on Tuesday morning.

In statements previously posted to Nxivm’s website, Raniere said all involved in the DOS subgroup were consenting adults and that Nxivm was not involved in what he called a “sorority.” The group has not responded to numerous requests for comment from PEOPLE.

In the fall, they denounced a New York Times article about them as “a criminal product of criminal minds.”

• With reporting STEVE HELLING