Ray Manzarek and Robby Krieger have signed on to help score Manson Girls, an upcoming film focusing on the female disciples of cult leader Charles Manson, Variety reports.

When the project was first announced at the 2011 Sundance Film Festival, it was revealed that Doobie Brothers members John McFee and Guy Allison would be composing the score to the movie, which recently began production.

In addition, the soundtrack reportedly will feature some of the flick's cast members performing classic songs of the era.  Estella Warren, Taryn Manning and Bill Moseley will be singing, respectively, The Animals hit "House of the Rising Sun," The Mamas and the Papas' "California Dreaming" and The Doors' "Five to One."

According to producer Susanna Lo, the film will focus on the time period before the infamous murders Manson's followers committed in 1969 and will try to shed light on how the woman involved with Manson came under his influence.

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