Amanda Seyfried was frightened by the ''harrowing'' violent scenes in 'Lovelace'.

The actress plays 1970s pornstar Linda Lovelace in the forthcoming biopic, and while she insists the nudity in the sexually-explicit movie did not faze her, she was terrified by the domestic violence involving her character.

Amanda told the Daily Mirror newspaper: ''It was a risky role to play, I suppose, but the nudity didn't scare me. I was more afraid of some of the violence and beatings she suffered, but she was a courageous woman and I've never been so affected by a role as I was by this.

''The story of Linda Lovelace's life is a very dark place to go. We couldn't show half of what she went through, although our film is still a pretty harrowing experience.''

The role makes a drastic change for Amanda - who played innocent beauty Karen Smith in 2004 comedy movie 'Mean Girls' - but she admits the part is her ''most rewarding experience'' in her career.

She added: ''In the past, I have had difficulty exposing my sensual side and feeling very shy and awkward about that side of me. But I've matured a lot over the last few years and it's a different world for me now. I think my self-image has improved a lot and I'm more at ease with who I am.

''But it was the most intense and rewarding experience I've ever had on a film.''

Despite the change of role, Amanda insists it was hard to bounce back from such a ''dark'' place.

She explained: ''I felt like I was detoxing for a few weeks after getting caught up in her world. It was a tough shoot but that's what I was looking for. I've played in several romantic kinds of movies but I've always been looking for darker roles.''

The film - which is due for release in August - tells the story of Linda being forced into porn by her violent ex-manager before becoming a feminist and anti-porn campaigner.