Jodie Foster: The Beaver was my greatest struggle
The film, which Foster both directed and stars in, also features Mel Gibson, Jennifer Lawrence, Michelle Ang and Anton Yelchin.
It focuses on a troubled man, who decides to use a beaver hand-puppet as his sole means of communicating.
Speaking at the SXSW Film Conference and Festival, the actress said: "This is not a comedy. The film reflects the struggle of one man in the midst of a spiritual crisis.
"This was the biggest struggle of my professional life."
The Beaver is not Foster's first project as director. She also worked on Home for the Holidays and Little Man Tate.
Foster has also netted two Oscars during her career, taking the best actress award for both The Silence of the Lambs and The Accused.
She was also nominated for the best supporting actress award for Taxi Driver and got the best actress nod for Nell.