'The Killer Inside Me' is a film based on the 1952 novel of the same name, by American writer Jim Thompson. Directed by Michael Winterbottom, it follows the story of Deputy Sherriff Lou Ford (Casey Affleck), a seemingly respectable member of his small hometown's community.
When Lou Ford is asked to railroad a talkative prostitute out of town before she makes trouble, he realizes it's easier to just get rid of her for good. Unfortunately, covering up that murder means eliminating more and more people as his problems and complications spiral out of control. Even worse, he's starting to enjoy committing the crimes a lot more than he ever enjoyed dishing out the punishment.