We were looking for someone who could get the film [Filth] made at that kind of level, with the finance we wanted, and we spoke to a lot of people. When I met James [McAvoy] in the Soho Hotel with Jon Baird, the director, he looked about ten years old. I thought there's no way he's going to be a forty-year-old divorced alcoholic cop. I thought, really lovely guy, I'll let him and John talk and see if they get on.

I'm not interested in details that might get someone into trouble. I'm more interested in generalities rather than the particulars, as a journalist would be. Names, dates and times don't interest me at all. I'm interested in feelings and emotions. Most people are game, once they realize that you're on the level as far as that's concerned and you're not about exposing them, then they feel quite free to talk about it. Police officers and social workers are no exception.

I feel like I've exhausted guys and male friendships.

Bowie's death is a very emotional thing. My generation of working-class Britain, it feels like we lost our spiritual leader, our guru. I always thought that if I was to be a hundred, somehow Bowie would be a hundred and fifteen. He'd be there to still steer me and guide me.

If it's something that I feel uncomfortable with, that's a reason for me to write it. I kind of like to make myself feel uncomfortable. I think if you're starting to feel uncomfortable with something when you're writing it, that's the reason really to push on with it.

In America I think we need to move towards a social democracy, European-style basically, and I think that in Britain we do as well.

There's nothing worse than a violent beating from an unremarkable person. Physical violence with someone is too much like shagging them. Too much id involved.