Brie Larson recalls secrecy behind 'Avengers: Endgame' on 'Tonight Show'

April 25 (UPI) -- Brie Larson discussed on The Tonight Show the challenges of filming Avengers: Endgame due to the secrecy surrounding the superhero epic.

Larson, who portrays Captain Marvel in the Marvel cinematic universe, detailed to host Jimmy Fallon on Wednesday how even the stars of Endgame are left in the dark about the film and must work with heavily redacted scripts.

The actress said she filmed Endgame first before her solo Captain Marvel outing, leading to more challenges.

"I arrived and they gave me a piece of paper that had like, it was a full page of dialogue and action but all of it was redacted except for my one line," Larson told Fallon. "It wasn't until I walked on set that I was like, 'Oh crap. I'm like in a Marvel movie right now."

Larson recalled how despite doing the scene, she didn't get to see the final end result until the end credits of Captain Marvel which featured herself arriving to meet the Avengers for the first time.

"I didn't know what that was that we were shooting. There was also nobody else there. I was by myself on a green screen," she said despite the end product featuring herself talking to Captain America (Chris Evans), Black Widow (Scarlett Johansson), War Machine (Don Cheadle) and Bruce Banner/Hulk (Mark Ruffalo.)

Avengers: Endgame is set to arrive in theaters on Friday.