Casey Affleck shines in the role of a bipolar serial killer who devotes his non-killing time between two women - Kate Hudson- his girlfriend and a prostitute played by Jessica Alba.

Casey is a West Texas Deputy Sheriff in the 1950's whose bipolarism has the town he lives in fooled.

By day he is the sweet kind deputy sheriff keeping the folks safe, by night he is a sick sado-masochist murderer.

The movies director Michael Winterbottom spoke to The Herald newspaper about his adaptation of Jim Thompson's 1952 dark thriller.

He has named it "The Killer Inside Me"

Winterbottom, an English director, said that making the film was not difficult.

"Once we decided we were going to stick to the book, when it came to trying to decide how to shoot a scene, it was a case of going back to the book and trying to find a way of doing that.

When the movie was shown at Sundance, several people complained about the violence on display.

Winterbottom was surprised at peoples reactions, which included walk outs.

"There are two elements to this that surprise me. Obviously, I wanted those moments to be shocking. What was surprising to me at Sundance was more the reaction of 'this is horrible. I don't want to watch this horrible scene. And I think it's immoral'. That element was shocking."

"The idea that it's immoral to show violence as something that is horrible, brutal and nasty, an somehow, the implication is that you can show this story about a man beating these women -- about killing them -- as long as it looks okay, as long as it's not disgusting. And that to me would be more immoral, just perverse. It's not more moral to show violence as being entertaining, or exciting, or acceptable. It's more moral to show violence as being horrible."

Bill Pulman and Ned Beatty also stared in the movie.

"All the other actors, apart from Casey, came in for just two or three days. We had a very weird structure where every scene was nearly always Casey with just one other person, and that person kept changing," said Winterbottom, who has produced a movie a year for the past ten.

"The Killer Inside Me" releases to limited engagement on June 18