HBO is on a roll with its recent lineup of true crime documentaries. First there was McMillion$ and Atlanta’s Missing & Murdered: The Lost Children, plus the stunning adaptation of the late Michelle McNamara's I’ll Be Gone in the Dark, about the search for the Golden State Killer. Now the network is capping off 2020 with The Vow, an in-depth exploration of the multi-level marketing scheme-cum-sex cult NXIVM.

There's still plenty of time to binge the first several episodes of the nine-part series, which will conclude on October 18, 2020. In the meantime, here are some facts to know about the group—and what to expect from the buzzed-about series.

1. The Vow centers on NXIVM's victims.

The Vow opens on documentary filmmaker Mark Vicente’s initiation into a seemingly innocent, if slightly unsettling, wellness empire on steroids that is reminiscent of The Secret or a religious cult. By the end of the first episode, Vicente’s wife, Star Wars actress Bonnie Piesse—whom he met through NXIVM—leaves the group amidst her growing concerns for its female members.

2. NXIVM has been around for more than 20 years.

Sashes denote ranks in NXIVM.Courtesy of HBO

NXIVM was founded by Keith Raniere and Nancy Salzman in 1998 as a multi-level marketing company for personal and professional growth. It followed a belt or sash system similar to karate that was known as the “stripe path.” For each level of achievement, wearers would graduate to a different color and number of “stripes” on their sash. It’s unclear what exactly these sashes indicated other than contributing to the mythos around NXIVM, and investing more money in the organization with dues, classes, and more.

3. NXIVM members called their leaders by unique titles.

In The Vow, many of the former NXIVM members interviewed—including Vicente and Sarah Edmonson, who both rose to the rank of a green sash—expressed discomfort at having to call their superiors Raniere and Salzman “Vanguard” and “Prefect,” respectively.

4. NXIVM was an umbrella organization.

NXIVM wasn't just a single company, but an umbrella organization with several other businesses operating under the main brand. Other psychobabble brands that came under NXIVM's umbrella were Rainbow Cultural Garden, a child care center, and Jness, which was described on its now-defunct website as "a women’s movement that facilitates an ongoing exploration of what it means to be a woman." Many of the women embroiled in the cult and who are featured on The Vow were recruited into NXIVM through Jness.

NXIVM's most shocking offshoot, and one that is a large part of The Vow's focus, was DOS. DOS stood for Dominus Obsequious Sororium, a Latin phrase that translates to “master over slave (women).” As The Vow goes on, it appears that Jness was the empowering front for DOS.

5. NXIVM was obsessed with celebrity.

Catherine Oxenberg, Mark Vicente, Bonnie Piesse in The Vow (2020).Courtesy of HBO

Global business and cultural icons like Richard Branson and possibly even the Dalai Lama have extolled NXIVM’s virtues in the past. Actresses such as Piesse and Smallville alumna Allison Mack were also focal points of both NXIVM and The Vow. Mack’s high-ranking position as the public face of Jness and (as is later revealed) DOS captured the public’s attention.

Dynasty star Catherine Oxenberg had some interactions with the group and in 2011, she and her daughter India signed up for one of the group's empowerment classes. "The truth is, what we went to was an intro for a leadership program," Oxenberg explained in 2019. "It could have been any self-help program, and that’s the truth. Nobody signs up to join a cult. These cults very often have consumer-facing companies offering real and viable resources and tools. And that’s what this was ... I thought that she might benefit from some leadership skills because she was going into the business world." India, however, became deeply involved with the group, including DOS, and several episodes of The Vow focus on Catherine's quest to rescue India from NXIVM.

6. Billionaires bankrolled NXIVM’s legal battles.

Billionaire heiresses to the Seagram fortune, Clare and Sara Bronfman, were embroiled with NXIVM and footed the bill for the organization's legal woes. Clare was sentenced to 81 months in prison in September 2020.

7. NXIVM co-opted the language of wellness and sisterhood to draw women into DOS.

Members were asked to count calories and lose weight, and it is repeatedly stated that DOS is a “sorority,” but we all know that one has to be initiated into a sorority. And DOS's version was something far more painful than most would-be sorority sisters would ever willfully endure.

8. To be inducted into DOS, would-be members were required to hand over "collateral."

Sarah Edmondson holding her NXIVM sash in The Vow (2020).Courtesy of HBO

In episode 3, Edmonson reveals that initiation into DOS required providing the organization with “collateral,” like the deed to one's home or incriminating photos, in order to demonstrate their allegiance to the sisterhood. The ultimate test was for a “slave” like Edmonson to be branded by her “master,” who in this case was Lauren Salzman, the daughter of NXIVM founder Nancy Salzman. (Edmonson has alleged that doctor Danielle Roberts performed the branding.)

9. DOS members were branded with their leaders's initials.

Brandees were told that the symbol that was burned into their skin, sans anesthetic, represented the Earth, air, and water, but it was actually the combined initials of “grandmaster” Raniere (KR) and Mack (AM). It wasn't the actual branding, but realizing what the brand stood for, that led Edmonson to leave the group. "It was when I figured out Keith’s initials were on my body and women were having sex with him; that this was not empowerment but slavery, and it was all built on lies," Edmonson said.

10. Keith Raniere and Allison Mack are still awaiting sentencing.

In April 2018, Mack was arrested and charged with sex trafficking, sex trafficking conspiracy, and forced labor conspiracy. She pled guilty to racketeering charges in 2019 and is awaiting sentencing. In 2019, Raniere was convicted of several crimes, including sex trafficking, sexual exploitation of a child and possession of child pornography, and conspiracy and conspiracy to commit forced labor. He will be sentenced in October.