Former Dynasty star Catherine Oxenberg’s daughter, India, was one of the reported sex slaves within NXIVM and DOS. With the arrest of the cult leaders, that nightmare is over.

Within the organization, women were allegedly blackmailed and branded at the behest of Keith Raniere and Allison mack.

In Catherine’s new book, she shares the harrowing details of what has been revealed to her about life within the nightmarish sex cult. Take a look:

RadarOnline has the scoop: Catherine Oxenberg’s new book is titled Captive: A Mother’s Crusade to Save Her Daughter from a Terrifying Cult.

That might sound like it’s melodramatic or, worse, the title of a Lifetime movie. But having a child trapped in a sex slave cult in which you don’t know what’s happening to them is frightening.

The only thing worse, perhaps, is when you finally learn what is happening. And that is what Catherine did as she consulted with multiple women about what they say happened.

Keith Raniere may be the leader of NXIVM, but Allison Mack was a “master” within the sex-slave cult.

“I would hear from many slaves that Allison was also very territorial about Keith,” Oxenberg writes in her book.

She was allegedly his fanatical servant, determined to please him by selecting women and ordering them to have sex with him.

But apparently this task made her feel jealous of the women who were, after all, obeying her orders.

“And,” Oxenberg writes, Mack “felt threatened and jealous of each woman she sent to have sex with him.”

“Which resulted in her being very punitive and sadistic as a master,” Oxenberg reports.

That makes a twisted kind of sense. If you’re providing someone with lovers because you’re devoted to him, you might also resent those lovers if you feel that you should be the one in bed with him.

Combine that with Mack being allegedly in charge of “discipline” for the slave women and you get a recipe for suffering.

In fact, Mack was said to be an incredibly strict taskmaster.

Oxenberg writes that Allison Mack is “obsessed with penance and weight.”

The slave women were reportedly subject to blackmail and other punishments while required to make themselves “perfect” for Raniere.

“They also had to give collateral every month,” Oxenberg writes. “And keep closely to their starvation diets.”

As we all learned late last year, Mack and the other women are said to keep themselves to starvation diets, limiting their caloric intake to an alarming degree and also exercising.

This is allegedly part of what they need for self-improvement or whatever, which makes it curious that Raniere himself does not do any of that.

Oxenberg also reveals some details of the tasks that Mack would allegedly assign to the slave women.

There was more to it, it seems, than a simple instruction for a woman to bed Raniere.

For one thing, it’s said that Mack would give them permission to enjoy the sex.

Additionally, Oxenberg writes that Mack would instruct the women to “let him take photos of you naked afterward.”

This was apparently “to prove you’ve completed this assignment.

Mack would allegedly order the women with naked photos to “send them to your master.”

Oxenberg apparently learned this from speaking with multiple former “slave women” from NXIVM’s internal group, DOS, which is an acronym for a latin phrase meaning “dominance over the slave women.”

We can only imagine the heartache that she must have felt — and must still feel — knowing that her own daughter was recruited and, incrementally, manipulated step by step until she was one of these women.

The heiress who bankrolled Keith Raniere and NXIVM tried to suggest that the abuse allegations are just sex-shaming, but the allegations aren’t that Raniere engaged in sex.

The allegations are that, through blackmail and brainwashing, Raniere and Mack gave this women no choice but to allow themselves to be branded and bedded at his will.