Wanting to be a good actor is not good enough. You must want to be a great actor. You just have to have that.

'Nil By Mouth' was a bit autobiographical, but as I always pointed out at the time, that's not my dad.

It's becoming increasingly harder and harder; there's no such thing as independent film anymore. There aren't any, they don't exist. In the old days you could go and get a certain amount of the budget with foreign sales, now everybody wants a marketable angle.

I applaud anything that can take a kid away from a PlayStation or a Gameboy. That is a miracle in itself.

And of course I've got kids of my own now, and they love me being in the Harry Potter films. I'm now part of a phenomenon. You become incredibly cool to your kids, and you get a young fan base. So you became the cool dad at school. You're suddenly hip.

I have three kids who like Harry Potter so I was sort of aware of it. You can't really move from it: it's on buses, in stores, it's everywhere. One of my kids has read the books; the other two are too small but they like the movies.

When you play a character that is so emotionally closed there are times when you ask yourself if you are doing enough and if it's reading. That is where you have a director, who is the barometer of what you are doing.