I should say, a piece of advice that was given to me very early on by the principle of RADA (Royal Academy of Dramatic Art) which is where I went. When he auditioned me, he said, "Your speech, monologue, is fine. It's good. Yeah, I think you have ability but you're making it happen. Don't make it happen, let it happen." And that's a sort of subtle shift I think, as an actor.

We're in a world of truncated sentences, soundbites and Twitter... [Language] is being eroded -- it's changing. Our expressiveness and our ease with some words is being diluted so that the sentence with more than one clause is a problem for us, and the word of more than two syllables is a problem for us.

I got to read some writings by serial killers, and they got inside my head. They were quite disturbing. I read disturbing stuff about that very detached way of manipulating people to do things.

The sets were fantastic. The Harry Potter sets are brilliant. You do get transported for a second.

I'm not very good at being domesticated. I've tried. The domestic life I find claustrophobic - the rituals and habits and patterns.

Actors use who they are to be someone else, but I would hate to ever think I'm playing myself. It's imagining being someone else that is the key motivating thing for me. So when people want to know about me, it makes me a bit unnerved.

The film depends on the audience's belief in this relationship.