The Amelie actress confessed that she has been looking for roles that are different from the young and innocent girl she played in her breakthrough 2001 film.
"It didn't exactly free me, but it did make more want to explore cinema even more," Tautou told The AP of her role as a killer wife in Therese Desqueyroux.
"I really liked the experience. I had to try to not be scared of Therese. I want to go to the darker side of humanity."
Tautou added: "I'm not the same woman I was when I was 22 years old. I don't feel genuine in young ingenue parts any more. Therese led me to entirely new terrain."
Therese Desqueyroux closed the Cannes Film Festival on Sunday (May 27) in memory of the late director Claude Miller, who passed away in April.
Watch a short teaser clip from Therese Desqueyroux below:
Photo gallery - 65th international Cannes Film Festival:
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