Mary Harron's influence on the film is most notable for what happened behind the scenes in the years of development and pre-production. Harron took over the film after Bret Easton Ellis's version of the screenplay didn't suit the original director's vision. Harron would go on to create a screenplay that would eventually be the version viewers found on screen. It had satirical elements in it that almost weren't in the film. The reason being that Christian Bale had been replaced by the studio with Leonardo DiCaprio who chose Oliver Stone as the new director. But after the new director and star couldn't agree on the direction of the film it reluctantly was given back to Harron and Bale.
Harron believed that Bale could portray Patrick Bateman in a way that would realistically create the narcissism needed on screen, and she was concerned DiCaprio's movie star fame would distract from the character she was attempting to capture. In the end Harron is able to notably reveal Bateman's horrific personality. Vanity, insanity, brutality, et al in a way that is frightening. The reason being that Batemen is rich, in great shape and his ability to lure people into his world is quite simple as many are attracted to wealth and good looks. This film became a call of sorts about the dangers of vanity and the violence of unchecked morality, which Harron shows well in Batemen's sterile and lonely apartment. Harron's version of the film has gone on to be a lasting favorite in the world of cinema by fans and many critics.
