courtroom sketch Keith Raniere
© Elizabeth Williams via AP
In this courtroom sketch Keith Raniere, second from right, leader of the secretive group NXIVM, attends a court hearing Friday, April 13, 2018, in the Brooklyn borough of New York.
A notorious guru self-helped himself to a bevy of sex slaves, subjecting them to "shame and humiliation," a federal prosecutor said Tuesday.

Keith Raniere - the sex svengali of the NXIVM cult - held sway over the vulnerable women by threatening to expose their "deepest, darkest secrets."

The women either agreed to have sex with him or they would be exposed.

Prosecutor Tanya Hajjar presented opening statements at the sex-trafficking trial of Raniere in New York City.

"The defendant pretended to be a guru," Hajjar said, "but he was a criminal."

The prosecution laid out a sordid indictment against Raniere who ensnared Smallville star Allison Mack, a Bronfman heiresses and a bevy of other starlets.

Nicki Clyne and her rumoured wife, Allison Mack
© INSTAGRAM
Alleged sex slave Nicki Clyne and her rumoured wife, Allison Mack. Both are members of the NXIVM sex cult.

Raniere had allegedly had sex with his first sex slave, a 15-year-old Mexican girl named Camila, and took nude photos of her. She described how some female followers were branded with Raniere's initials.

"This was organized crime. Keith Raniere was an organized crime boss," Hajjar told the jury of eight men and four women in her opening statements.

The prosecutor said that Raniere brought Camila and her two sisters to live in New York in 2005. He had promised to mentor them.

"[But] the defendant wasn't interested in mentoring," said Hajjar. "Instead, he had sex with all three daughters."

Raniere began sleeping with Camila, the youngest sister, and nicknamed her "Virgin Camila."

When he discovered one of the sisters was in love with someone else, he locked her in a room for two years before banishing her to Mexico, Hajjar added.

As Raniere's first "slave," Camila was urged to recruit other slaves to sleep with him. An actress named Nicole's first introduction to Raniere came while "blindfolded and tied to a table."

Hajjar said: "A third person came into the room and started performing oral sex on her. That third person was Camila."

Some were also burned with Mack's initials. Her role in the cult has been characterized as the svengali's main recruiter and second banana.

Cops say the branding was done using a cautery pen without anesthesia by a doctor who is now under investigation by state health officials.

Eight "Jane Does" in that case have refused to answer questions, saying through their lawyers "the branding was a voluntary free expression of personal beliefs."

Five of Raniere's co-defendants, including TV actress Mack, have pleaded guilty and she is expected to testify against her former lover.

Actress Allison Mack leaves Federal court
© Mary Altaffer / AP
Actress Allison Mack leaves Federal court, Wednesday, July 25, 2018, in the Brooklyn borough of New York City.
Raniere denies criminal wrongdoing; his lawyers say his relationships were consensual.

In court papers, defence lawyers have said the alleged victims were never abused.

The women were instead described as "independent, smart, curious adults" in search of "happiness, fulfilment and meaning."

But legions of NXIVM defectors and detractors have called the self-help rhetoric a brainwashing device that has destroyed lives.

In his opening statement, defence lawyer Marc Agnifilo said his client's actions were designed to help people.

He called Raniere "misunderstood" and that the alleged victims were never forced to do anything against their will.

Raniere has pleaded not guilty to the charges in federal court in Brooklyn. The trial is expected to last six weeks.