Casting is really a black art. It's a huge part of directing and it's the most invisible. It's one that people don't really think about or talk about. But you can really destroy your movie by casting it badly before you've shot a foot of film. And yet there are no guidebooks for it, there's no rule book to tell you how to do it. It's all your own experience and your own sensibility and your own intuition.

I have no rules. For me, it's a full, full experience to make a movie. It takes a lot of time, and I want there to be a lot of stuff in it. You're looking for every shot in the movie to have resonance and want it to be something you can see a second time, and then I'd like it to be something you can see 10 years later, and it becomes a different movie, because you're a different person. So that means I want it to be deep, not in a pretentious way, but I guess I can say I am pretentious in that I pretend. I have aspirations that the movie should trigger off a lot of complex responses.

I work with my dreams or nightmares.

But with my last film, Spider it was agony. The money was always disappearing, nobody got paid, it was very difficult - and it's very distracting from the process of making the movie, of course. So I think things have been getting harder and harder.

All romances end in tragedy. One of the key people in a romance becomes a monster sooner or later.

I also think the relationship I have with my audience is a lot more complex than what Hitchcock seemed to want his to be - although I think he had more going on under the surface as well.

Let's put it this way, when I was casting, I cast Viggo first and then found someone who could play his wife, rather than the other way around. So for me he's still the lead character.