Brad Pitt and Margot Robbie Have a Once Upon a Time Reunion in Babylon First Look Photos

Paramount Pictures

Brad Pitt and Margot Robbie are back, bringing more Hollywood history to the big screen.

In this December's Babylon, Pitt and Robbie — who co-starred together in 2019's Once Upon A Time...In Hollywood and also both appeared in 2015's The Big Short — reunite, playing stars in Los Angeles in the 1920s when the movie business was transitioning from silent films to talkies.

Oscar-winning writer/director Damien Chazelle (La La Land, Whiplash) told Vanity Fair that Pitt, 58, and Robbie, 32, found their fictional roles especially relatable.

"Part of what was magical about working with them in these roles is that each of them felt like they were really able to make the performance the most personal thing they had done," he said.

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Scott Garfield/Paramount Pictures

Robbie plays up-and-coming actress Nellie LaRoy who is inspired by performers like Joan Crawford, Clara Bow and Jeanne Eagels. Chazelle said, "Margot as a person has this — it's a very Australian sort of thing — brash, bold, hungry kind of edge to her that she was really able to tap into and do a lot of really fun things with."

As Chazelle explained, Pitt plays the character Jack Conrad, an "über-movie star" inspired by real-life icons such as Clark Gable, John Gilbert and Douglas Fairbanks. The director said of the character, "He's reaching a point in his life in his career where he's starting to look back and starting to wonder what's ahead."

Paramount Pictures

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The cast also includes newcomer Diego Calva, Jovan Adepo, Li Jun Li, Jean Smart, Tobey Maguire, Max Minghella, Lukas Haas, Olivia Hamilton, Rory Scovel, Katherine Waterston, Flea, Jeff Garlin, Eric Roberts, Ethan Suplee, Samara Weaving and Olivia Wilde.

Paramount Pictures

According to an official log line, the film is "a tale of outsized ambition and outrageous excess" that "traces the rise and fall of multiple characters during an era of unbridled decadence and depravity in early Hollywood." Chazelle told Vanity Fair that Babylon is "definitely the hardest thing I've done" so far in his career.

"Just the logistics of it, the number of characters, the scale of the set pieces, the span of time that the movie charts — it all conspired to make it particularly challenging, but it was a challenge that was pretty exciting to take on," he said.

Babylon is in select theaters Dec. 25 then everywhere Jan. 6.