The Lifetime TV movie, Manson's Lost Girls, depicts the little-known world of the infamous Manson family, and ET talked to the cast about how they embodied their characters.
The film paints a new picture of Charles Manson's world, through the story of Linda (Mackenzie Mauzy), who gets swept up in the acceptance of the Spahn Ranch hippie commune in the 1960s. After meeting Manson (Jeff Ward) at the commune, she becomes taken with him and gets drawn her into his web of criminal activities, which included stealing from lavish homes and the brutal death of actress Sharon Tate.
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In the end, Linda breaks away and turns herself in as a witness for the prosecution and helps convict Manson.
Manson's lost girls -- Patricia Krenwinkel (played by Isabel Shill), Leslie Van Houten (played by Kelsey Grammer's daughter, Greer Grammer) and Susan Atkins (played by Josh Brolin's daughter, Eden Brolin) -- each are serving life sentences for murder, but the actresses playing them captured more than just the dark side of these women.
"Susanne Atkins is just such a character," Brolin told ET. "She's wonderful and beautiful and ugly and loyal. I just wanted to play her. I was excited to get into her shoes."
Grammer portrays the former homecoming queen, Van Houten, and she explained that the project might not be appropriate for all ages.
"There's definitely a good amount of drug use," Grammer said. "You see us smoking a lot. Drugs are a very big part of who these people were, so it's a big part of the movie."
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Christian Madsen, son of Michael Madsen, plays central Manson family member Tex Watson, and he explained what attracted these men and women to one of the most infamous cults of all time.
"All these people are looking for acceptance and looking for guidance," said Madsen.
ET spoke to Manson in prison in 1989, where he gave his side of what the family was all about.
"A bunch of children were giving their lives for something they believed in," he said at the time. "It was an episode with a lot of different reasons. Susie had one reason. Leslie had another. Leslie told the court, 'At least you won't be sending your children to Vietnam.'"
Manson's Lost Girls airs Feb. 6 on Lifetime.