Leonardo DiCaprio, Brad Pitt reveal suave retro look for Once Upon a Time in Hollywood

Leonardo DiCaprio has given fans a sneak peek at his new film Once Upon a Time in Hollywood, sharing a photo of himself and fellow cast member Brad Pitt on social media.

In the image posted to Instagram on Wednesday, the Titanic star can be seen standing alongside Pitt, both decked out in '60s fashion.

DiCaprio simply captioned the picture, "First look. #OnceUponATimeInHollywood"

Looking suave, DiCaprio squints at the camera in an orange leather jacket with mustard turtleneck and brown pants, while Pitt casually leans against a pillar in double denim and sunnies, reports news.com.au.

The film is set in 1969 Los Angeles "at the height of hippy Hollywood", according to director/writer Quentin Tarantino.

The story is centred around the infamous Manson Family murders and that of former TV Western star Rick Dalton (played by DiCaprio) and his stunt double Cliff Booth (Pitt) as they struggle to make the transition into the film industry.

Dalton was a neighbour of Sharon Tate, an actress who was murdered by Charles Manson's followers.

Australian actress Margot Robbie has been cast as Tate. She previously appeared alongside DiCaprio in Wolf of Wall Street in 2013.

Once Upon a Time in Hollywood's all-star cast also includes Al Pacino as Dalton's agent, as well as Burt Reynolds, Luke Perry, Emile Hirsch, Dakota Fanning and Nicholas Hammond among others.

Tarantino has worked with both Pitt and DiCaprio in the Oscar-nominated films Inglourious Basterds and Django Unchained respectively.

According to the Hollywood Reporter, Tarantino called the pair's casting "the most exciting star dynamic since Paul Newman and Robert Redford".

The movie is scheduled for release on August 9, 2019 — the 50th anniversary of Tate's murder.