Regarding the movie American Psycho....
Excerpt from Wiki:
http://en.wikipedia.org/wiki/American_Psycho_(film)
Interpretation
There are two common interpretations regarding Patrick Bateman's acts of violence in the film. One is that the murders he commits are in fact real, but the self-obsessed and presumptuous nature of the people surrounding Bateman permits him to escape responsibility. For example, Patrick frequently confesses to people, and they either do not notice or hear something else. Frequent cases of mistaken identity also seem to work towards such an advantage. The final scene at Paul Allen's apartment is another clue, as it has been freshly painted and carpeted. The woman showing the apartment shares an uneasy moment with Bateman, insinuating that the building owner cleaned up the mess and disposed of the corpses in order to sell the apartment more easily. The greed, materialism and shallowness of the wealthy high-society leave Bateman "unable" to get caught, in spite of his attempts to confess.
The other interpretation is that some or all of the murders and debaucheries merely take place within Batemans imagination, like a darker, more sinister Walter Mitty. This interpretation is supported by the growing surrealism in Bateman's crimes as the movie progresses. In his final crime spree, a kitten inexplicably walks up to him while he is at an ATM; the ATM then demands that he "Feed me a stray cat." After confessing to his lawyer over the phone that evening, Bateman discovers the next morning that his lawyer thought it was a joke, and, in fact, does not even realize that he is Bateman, mistaking him for a different faceless businessman with his firm. Additionally, after murdering Paul Allen, Bateman drags him out of his lobby in an overnight bag, leaving an enormous trail of blood that inexplicably disappears moments later as he stuffs the bag into a cab. Lastly, Patrick's lawyer claims to have had dinner in London with Paul Allen long after the murder, though this may just reflect his inability to distinguish between financiers, as displayed seconds earlier when he misrecognized Bateman.
On the DVD commentary, screenwriter Turner's interpretation is that Bateman does in fact commit a few murders but aren't as glamorous as the movie depicts. For example she states that the prostitutes in reality wouldn't be as attractive and he wouldn't have killed one with a chainsaw.
