Chace Crawford has joined the cast of the Charles Manson biopic 'Charlie Says'.

The 32-year-old actor - who is best known for starring as Nate Archibald in 'Gossip Girl' - is set to star alongside 'Doctor Who' star Matt Smith as the titular character in the new biopic based on the infamous cult leader, The Hollywood Reporter say.

Crawford will star as Tex Watson, one of the murdering members of the Manson family who was involved in the brutal killing of pregnant actress Sharon Tate.

The movie will be helmed by the 'American Psycho' duo of director Mary Harron and screenwriter Guinevere Turner.

The film is based on a combination of the novel 'The Long Prison Journey of Leslie van Houten: Life Beyond The Cult', which was penned by Karlene Faith, as well as 'The Family' by Ed Sanders.

'The Family' will tell the story of a grad student who works with three brainwashed young women who formed part of the Manson family, Leslie Van Houten, Patricia Krenwinkel and Susan Atkins.

The movie will unfold via a series of flashbacks after each of the women finds themselves locked up in a special security unit at the California Institute for Women.

Hannah Murray, Odessa Young, and Marianne Rendon have also been cast to play the parts of the three young women who were sentenced to death following the infamous murder case of Manson.

However when the death penalty was lifted, their sentences became life imprisonment and a young graduate student, Faith (Merritt Wever), was sent to in to teach them, and the film follows the girls' transformations as they come to face the realities of their crimes.

This marks one of many Manson-themed movie projects in the works with Quentin Tarantino helming 'Once Upon a Time in Hollywood' starring Leonardo DiCaprio and Brad Pitt.