The film takes place in Los Angeles in 1969 and follows an actor and his stunt double as they attempt to find success in a changing Hollywood landscape.
DiCaprio's snap sees the actor and Pitt standing side-by-side in period ensembles, with DiCaprio in an orange jacket, yellow turtleneck and brown pants, while Pitt sports a denim jacket, jeans and sunglasses.
It's unclear whether the movie has already started filming or if the photo above is from pre-production and meant to share a taste of what viewers can expect from the period film.
Once Upon a Time in Hollywood is Tarantino's ninth film, and reteams both actors with the director after DiCaprio starred in 2012's Django Unchained and Pitt fronted 2009's Inglourious Basterds.
In the upcoming film, DiCaprio plays Rick Dalton, the former star of a Western TV series while Pitt is his longtime stunt double, Cliff Booth. DiCaprio's character lives next to Sharon Tate, played by Margot Robbie, and the film will include the Manson murders, in which Charles Manson's followers killed Tate and several others.
The film reportedly has a Pulp Fiction vibe and also stars Al Pacino, James Marsden, Dakota Fanning, Kurt Russell, Timothy Olyphant, Damian Lewis and Luke Perry, among others.
"I've been working on this script for five years, as well as living in Los Angeles County most of my life, including in 1969, when I was seven years old," Tarantino said in a statement in February, via The Hollywood Reporter. "I'm very excited to tell this story of an L.A. and a Hollywood that don't exist anymore. And I couldn't be happier about the dynamic teaming of DiCaprio & Pitt as Rick & Cliff."
He also described the film as "a story that takes place in Los Angeles in 1969, at the height of hippy Hollywood. The two lead characters are Rick Dalton, former star of a Western TV series, and his longtime stunt double Cliff Booth. Both are struggling to make it in a Hollywood they don't recognize anymore. But Rick has a very famous next-door neighbor … Sharon Tate."
Once Upon a Time in Hollywood is set for release on August 9, 2019.
Photo Credit: Getty / Gabe Ginsberg