Eva Green: Sin character is evil

Eva Green says her Sin City character is a "real b***h".

The French actress takes on the role of femme fatale Ava Lord in action thriller Sin City: A Dame to Kill For.

It's a guilty pleasure for the 33-year-old, who has nothing in common with her ruthless character.

"She's most evil," the star admitted to Total Film when asked if Ava is the most violent role she's ever taken on. "She has no sense of morality. There's nothing holding her back. She's a real b***h! It's so far from me, and just so irreverent."

Eva adds that Ava gets what she wants by seducing men and transforming herself into their "deepest desires".

Using her power like that was something the actress couldn't identify with and found exhausting at times.

"I was very worried because my character is so many characters; sometimes I felt like I needed to know whether Ava was lying or whether there was a shred of truth in what she was saying," she explained.

"She's sick in the head! She would lie all the time. You don't know if it's sincere! It was a challenge for me to look still believable. Do people see that she's lying? It's a very fine line."

Sin City: A Dame to Kill For co-stars Joseph Gordon-Levitt, Jessica Alba and Bruce Willis. Eva joined the cast late, which wasn't ideal for her.

"I was cast rather last minute, so it was rather stressful," she confessed. "Very intense. I had five days of prep. Usually, I'm a nerd - I like to prep - but this was like, 'Woah, good luck to you!'"