Allison Mack, the 'Smallville' actress who was a member of the sex cult NXIVM, was seen breaking down in tears as she sang a love song for cult leader Keith Raniere on his birthday. The creepy video shows an emotional Mack struggling to keep it together while she performed a version of 'I Love You More Than You'll Ever Know' by Donny Hathaway. The actress unexpectedly pleaded guilty to her involvement in the group, in which women were branded on their groins, earlier this week.

Raniere is currently facing multiple federal charges that include sex trafficking. He was spotted in the audience watching the a cappella performance which happened in approximately the same time that Mack began recruiting women for DOS, which is an elusive master-slave sect at the heart of the cult, The Sun reported.

In the bizarre video, Mack can be seen barefoot and wearing a loose white dress as she sings the love song for the cult leader along with a group of backing singers. Mack is currently facing up to 40 years behind bars for her involvement. She can be seen crying as she sings: "I am only flesh and blood but I can be anything you demand."

Frank Parlato, the man who first published the video on his blog Frank Report, said that the footage had been taken at around the same time that Mack started her "criminal behaviors". Mack confessed earlier this week to being a part of DOS and admitted that she kept a "slave" and that she instructed women in the group "to perform services for me". The prosecutors have also alleged that women in DOS were kept on starvation diets and have been groomed to have sex with Raniere.

Former members of the group have also spoken about how they were held down while they were branded with both Raniere's and Mack's initials with a cauterizing iron. the women were also allegedly forced to give damaging collateral such as naked pictures, confessions, and other financial information, aside from having sex with Raniere.

Parlato told The Sun: "This performance takes place on Raniere's birthday during the 2016 Vanguard Week, an annual event dedicated to him, and you can see she is deeply moved. She's singing these words that are especially meaningful to him — and I think what is particularly intriguing about the video is that it was taken in 2016. By then DOS had begun. When she pleaded guilty this past week she admitted that her criminal behaviors began about this time. So her singing barefoot in front of Raniere shows the depth of her complete integration into the cult of Keith Raniere."

The man first exposed the branding of the women and worked day and night to expose the sick cult. He said it's a major turn on for the star, who has now publicly turned against her former master. He said: "She has made a 100 percent denunciation of Raniere now but that could be based on practical considerations."

Parlato continued: "He is going to go to prison for a very long time — she is facing a shorter or longer time depending on how much help she provides to the prosecution. She had signed a 10-page cooperation agreement with the US government to help their prosecution against the remaining defendants — including Raniere. I think the turning point for a lot of his supporters was when the government discovered a hard drive at his home containing explicit pictures of a 15-year-old Mexican girl. When that evidence came in everyone gave up on Raniere — including Allison. She knew that she didn't want to go down with the ship."

Mack, who pleaded guilty to racketeering and racketeering conspiracy charges that included extortion and forced labor, is currently facing a maximum of 40 years in jail but according to Parlato, she will most likely get around five years. He then believes the once-successful actress will try to renew her career.

Parlato concluded: "The maximum sentence is 40 years but she won't get that — she's more likely to get around three to five based on US sentencing guidelines for the crimes she has confessed to and her lack of criminal background. I think her lawyers are going to now try to get her sentence down to two years or less and try and get her qualified for home arrest. Or she'll try and get a low-security prison where she won't be subject to unduly harsh living conditions. After that, I think she'll try making a comeback with a strong defense that she was brainwashed and that she followed Raniere with the best of intentions."

You can watch the video HERE.