Margot Robbie and Brad Pitt's Old Hollywood Movie Babylon Is Over 3 Hours Long: Report

Scott Garfield/Paramount Pictures

Margot Robbie's next movie is jam-packed.

Robbie, 32, stars in Babylon, from La La Land and Whiplash director Damien Chazelle, as an aspiring actress named Nellie LaRoy in 1920s Hollywood, when the movie business was transitioning from silent films to talkies. Brad Pitt plays Jack Conrad, a movie star at a different stage of his career.

According to a report from Variety, Babylon has a total runtime of 3 hours and 8 minutes.

This will be the Oscar-winning director's longest film yet: 2014's Whiplash is 106 minutes, 2016's La La Land is 128 minutes, and 2018's First Man is 141 minutes.

The film is, according to an official synopsis, "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."

RELATED: Margot Robbie and Brad Pitt Play 1920s Hollywood Stars Ready to 'Party Forever' in Babylon Trailer

Scott Garfield/Paramount Pictures

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

Chazelle previously told Vanity Fair this film is "definitely the hardest thing I've done." He explained, "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."

Scott Garfield/Paramount Pictures

At the Toronto Film Festival, the director said after existing in the "quietness" of his space movie First Man, he "wanted to do something big, boisterous and loud," according to Variety. During that September appearance, Chazelle mentioned he was still in post-production on Babylon and "I'll be very happy to finally finish it."

Babylon is in theaters Dec. 23.