Sarah Edmondson said she thought she was getting a tattoo when she willingly participated in strange initiation ritual for a sorority that she says is associated with NXIVM.

20/20 Apr 27 Part 2: Inside the troubled past of NXIVM founder Keith Raniere

Before founding NXIVM, Keith Raniere started an ill-fated network marketing company Consumers' Buyline.

Where the secretive organization NXIVM case stands

On Monday, TV actress Allison Mack pleaded guilty to federal charges of racketeering related to her involvement in self-help group, NXIVM.

The Time I Went To a NXIVM Mixer/Recruitment Party

I attended a NXIVM Recruitment Party/Mixer in February 2007 in Hamden, Connecticut in which I met Stormy Daniels as Well as some High Powered Politica...

Couple in 'Gone Girl' case open up about night of attack, being accused of hoax

Denise Huskins was kidnapped from her boyfriend's bed on March 23, 2015, and authorities at the time were suspicious of her disappearance.

The Man Who Blew the Whistle On Alleged Sex Cult Inside NXIVM (HBO)

The story of alleged cult NXIVM has all the makings of a binge-worthy docuseries. A secretive leader who allegedly had women branded with his initials...

20/20 Apr 27 Part 1: Woman recalls being branded as part of joining secret society

Sarah Edmondson says the branding includes the initials of actress Allison Mack whom she learned was a high-ranking member of the society.