The 41-year-old’s eyes widened as Brooklyn federal court Judge Nicholas G. Garaufis announced her 81-month stint — after he laced into her for an hour, saying she used her deep pockets to help silence the group’s victims and critics.

The scion had “used her incredible wealth and attempted to use her social status and connections not only to support Nxivm’s work, but also as a means of intimidating, threatening, and exacting revenge upon individuals who dared to challenge its dogma,” he said.

Dressed in a pink shirt, billowy black pants and a floral face mask, Bronfman — who had been under house arrest at her city luxury apartment and owns an island in Fiji — was immediately taken into custody by US Marshals.

Bronfman pleaded guilty last year to charges of conspiracy to conceal and harbor an illegal alien for financial gain and fraudulent use of identification, admitting she committed credit card fraud on behalf of cult leader and convicted sex-trafficker Keith Raniere.

But prosecutors have said that Raniere — who ran a master-slave group within Nxivm called DOS, where women were branded with his initials and forced to sleep with him — could not have committed his crimes without the help of Bronfman and her $210 million fortune.

Before her sentence was handed down Wednesday, nine women who were victimized by Nxivm also tore into Bronfman, calling her a “dangerous megalomaniac” and “predator.”

According to the judge, federal sentencing guidelines had called for Bronfman to receive up to 27 months behind bars, while prosecutors had sought five years.

Bronfman’s own lawyers had sought three years of probation, denying she knew anything about DOS.

But Garaufis — who also ordered a $500,000 fine — wasn’t swayed.

“Ms. Bronfman came to learn details about DOS and faced a choice as to whose interests she would protect: Raniere’s or his victims’,” the judge said. “She chose Raniere unequivocally, and to this day she has not clearly apologized.”

Her lawyer said he would immediately appeal.

“The decision was clearly an abomination. It was outrageous. It was a miscarriage of justice, to go three times above the sentencing guidelines was totally uncalled for,” said attorney Ron Sullivan.

Bronfman is the first top Nxivm member to be sentenced in the case. Five others, including Raniere and former “Smallville” TV actress Allison Mack, who pleaded guilty to racketeering and conspiracy charges, are still awaiting their fates.

As a high-level member of Nxivm, Bronfman brought young women into the country illegally, prosecutors said.

Bronfman, once a top equestrian with her sights set on the Olympics, recruited one wannabe professional horse-rider into Nxivm — but the woman was eventually groomed for Raniere’s perverted sexual pleasure, according to court testimony.

The woman told the court during Raniere’s trial that she became a “slave” in DOS — then was ordered to “seduce” Raniere.

Prior to being sentenced, a tearful Bronfman gave a statement to the court, in which she admitted to making “mistakes.”

“I’m immensely grateful and privileged that people all over the world are praying for me because they know my goodness,” she said.

“It doesn’t mean I haven’t made mistakes, I have made mistakes…”

She then directly addressed one of her victims, identified as Jane Doe 12, an immigrant from Mexico who Bronfman recruited to work for a Nxivm-affiliated company — while refusing to pay her a living wage.

“I’m truly sorry for all your hardship and pain I have caused,” Bronfman said, her eyes welling with tears. “I hope you can forgive me and live a happy life.”

But the judge didn’t buy Bronfman’s mea culpa, appearing to see it as a continuing manipulation of the victim.

“Jane Doe 12 was affected by that. Bronfman is doing again what she did then. This judge is not blind Ms. Bronfman. I saw what you just did and I’m speechless,” he said, before shaking his head.

Raniere, 60, who was found guilty of charges including racketeering and sex-trafficking last year, faces up to life in prison when sentenced next month.