American Psycho ending has finally been explained after dividing opinion for nearly 25 years

If you've ever watched the cult classic American Psycho then one thing you'll be able to agree on with everyone is that Patrick Bateman (Christian Bale) is a f**king nutjob.

Over the course of the film we see him murder a bunch of people, try to feed a cat to a cash machine and get really sweaty over a business card.

It's made clear early on that Bateman's not entirely in the right state of mind. The movie continues his standard excuse of having to return some videotapes isn't going to cut it any longer.

However, even after having a shootout with police where he blows up their car and confesses to his crimes he seems to basically get away with the whole thing and the people around him still pay him barely any notice to the point that some of them don't even seem to remember his name.

The ambiguity is part of the point, since in the film Willem Dafoe's character would play his role in three different ways and the footage would be spliced together, making it hard to get a read on what he really knew.

The film is called American Psycho, you'd expect it to be about an American psycho. (Lionsgate Films)

At the end of American Psycho, Batemen tries to confess to his lawyer he's told that his first murder victim Paul Allen (Jared Leto) isn't dead, making the audience not sure on what they believe.

Viewers are left pondering if Patrick did any of it or whether he lives in a world so vapid and superficial that it generally doesn't care to know which preening prick in a suit is Patrick Bateman or what he gets up to.

American Psycho's director and screenwriter have talked about the movie's ending and what they intended to do with it.

According to Looper, American Psycho director Mary Harron said she didn't want audiences coming out of the movie 'thinking that it's all a dream', saying she 'never intended it'.

It would seem like he did do the things we see him do, but perhaps it didn't always go down the way he imagines.

Screenswriter Guinevere Turner (right) said 'everything was really happening' but Patrick's perception of events strays as he loses his mind. (Lionsgate Films)

The film's screenwriter Guinevere Turner, who also appeared in front of the camera, told YahooMovies that Bateman was 'going nuts' and the way he sees things isn't always the way we see them.

She said: "Everything was really happening. But at some point, we’re starting to see things through Patrick’s eyes.

"He’s losing his mind. So for example, in the scene where he gets the two hookers to come over, and he’s videotaping himself and looking at himself in the mirror – in real life, they probably they weren’t as attractive as they are, and it wasn’t all as Penthouse Letters as it is.

"So that’s where we start getting into Patrick’s head. And then by the time the ATM says ‘Feed me a stray cat’ – he’s there, he’s got the kitten, but the ATM doesn’t actually say that. He’s just going nuts. And then he’s unravelling from there."

Turner said that 'he did do all this stuff' but since he's so nuts and 'unravelling' not everything he sees is quite what's happening.

Make sense?