Brad Pitt and Leonardo DiCaprio will star together in Quentin Tarantino's Charles Manson movie.

Brad Pitt

Brad Pitt

The two stars' casting in 'Once Upon a Time in Hollywood', which will centre around the murder of pregnant actress Sharon Tate - the wife of director Roman Polanski - who was stabbed to death by members of the Manson Family in August 1969, was announced by Sony Pictures on Wednesday (28.02.18), with Leonardo playing the previously-rumoured part of an aging actor, and Brad his stunt double.

Tarantino described the movie as "a story that takes place in Los Angeles in 1969, at the height of hippy Hollywood. The two lead characters are Rick Dalton (Leonardo DiCaprio), former star of a western TV series, and his longtime stunt double Cliff Booth (Brad Pitt).

"Both are struggling to make it in a Hollywood they don't recognise anymore. But Rick has a very famous next-door neighbour...Sharon Tate."

Margot Robbie is rumoured to be in line to play Sharon, while Tom Cruise has also been linked to the project.

Both Brad and Leonardo have worked with the director before, on 'Inglorious Basterds' and 'Django Unchained', respectively.

The movie will be 43-year-old Leonardo's first project since his Oscar-winning turn in 'The Revenant', while Brad, 54, was last seen in 'War Machine' last year.

Sharon was eight months pregnant when she was brutally murdered.

The notorious cult leader had ordered a group of his followers to attack the inhabitants of a Los Angeles house which he believed was owned by a record producer who had rejected him and over the course of several hours, the quartet used guns and knives to kill the actress and four other occupants.

In 1971, Manson - who died last year - and other members of his group were sentenced to life in jail for the killings, as well as a number of other murders committed that summer.

'Once Upon a Time in Hollywood' is scheduled for release in August 2019.