England is strictly class-based. What's surprising is how many films are still made with a load of people in silly frocks running around gardens and talking in middle-class accents.

One of the great joys of my job is that you spend a huge amount of time investigating different areas of literature.

I love test screenings. Some directors don't, I know. But I love it. I think it's because I come from the theatre and in the theatre, previews are where you really have to listen to the audience and really feel how they're responding. I found our test screenings incredibly useful.

It's disingenuous to say that criticism doesn't get to you or you don't hear it or that you ignore it. When everybody says, 'That's crap. I hated that,' you hear it. But it's much, much worse when they're right: when you feel that it is an absolute piece of tosh. I made the film I wanted to make, so you just have to find a way of getting over it.

Actually, to be honest, this is a useful time to not be knowing what I'll be doing in 2013 or 2014, because really, for the last however many years, I've known what I've been doing for years and years ahead. You get into a cycle of non-reflection, and that gets a bit scary.

I never want to make a film. I don't wake up in the morning going, 'Ooh, I'd really love to be on set making a film today'. I'm aware that other contemporary film directors perceive film-making as what they do, as what they have to do. But I would hope that I am more catholic in my tastes.

I spent a little time in Germany as a schoolboy learning German, and it's a country I knew very well, spent a lot of time in. I knew the history very well. I've always wanted to do a piece of work about the post-war period, of one sort or another.