After signing on to portray Carol Danvers in the Marvel Cinematic Universe, Brie Larson's first turn as Captain Marvel came not in her own solo film, but Avengers: Endgame, where she found herself often unsure of just what she was meant to film for the day.

Marvel Studios has always been known for its secrecy, but the measure that it took with the two most recent Avengers films is easily more extreme than anything else the studio has ever done. In fact, the stars of both Avengers: Infinity War and Avengers: Endgame have confirmed that they did not receive actual scripts for the film. This threw Larson for a loop when she arrived in Atlanta for filming. "I flew to Atlanta for my first day on 'Endgame,'" Larson told Inquirer. "I had no idea what I was shooting, what the movie was. I didn’t know if anybody else was in a scene with me. I didn’t know anything."

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"And it’s not until you show up that you get your pages for the day," she continued. "But you only get your part. So it was like a scene that was completely black redacted, and then just my one line."

While it's clear Larson, like the rest of the cast, doesn't entirely know what happens in Endgame, the film will likely break $1 billion, becoming her second film this year to do so.

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Directed by Anthony and Joe Russo, Avengers: Endgame stars Robert Downey Jr., Chris Evans, Mark Ruffalo, Chris Hemsworth, Scarlett Johansson, Jeremy Renner, Don Cheadle, Paul Rudd, Brie Larson, Karen Gillan, Danai Gurira, Benedict Wong, Jon Favreau and Bradley Cooper, with Gwyneth Paltrow and Josh Brolin. The film arrives April 26.