Carey Mulligan has said that working with the Coen brothers on Inside Llewyn Davis taught her how to swear and be nasty.
The An Education star appears in the film about a young folk singer played by Oscar Isaac and said directors Joel and Ethan Coen had to bring out her bad side in filming.
She told The Wrap: "They pushed me to be nastier and scream louder and say more swear words. I was completely relaxed. I didn't think about my accent, I didn't think about anything.
" It was so cathartic, especially coming off [The Great] Gatsby.That was the only really big film that I'd ever done, and I wasn't used to working in that way. It was also the only film where I've played a character who's meant to be pretty. So that was sort of a bizarre stress and something that I had to think about in a visual way. It was kind of weird for me."
Carey admitted that playing a scruffier, nastier character for Inside Llewyn Davis was exactly what she needed after her Great Gatsby experience.
She said: "To come off that film and just put on a big black dark wig, no make-up and just sort of march around was great. It was like stomping around in the mud after being in a pretty dress, which was exactly what I wanted to do."
The 28-year-old also said that she appreciated being one of a privileged group who got to work with the Coens.
She said: "Being in a Coen brothers film feels elite. The kind of actors that get to be in their films, you just don't imagine you'll ever end up in that group."
Inside Llewyn Davis is due to be released in cinemas on January 24.