I knew with Snape I was working as a double agent, as it turns out, and a very good one at that.

On the screen were some flashback shots of Daniel, Emma and Rupert from ten years ago. They were 12. I have also recently returned from New York, and while I was there, I saw Daniel singing and dancing (brilliantly) on Broadway. A lifetime seems to have passed in minutes.

I never expected to have any kind of film career, to be honest. It was all a bit of a surprise. But I was in a big hit play on Broadway. America, as many people will say, says yes more often than we do. And so I was suddenly surrounded by people saying yes. But I was aware that was 'cause of what I was in. It had a big impact.

Acting is mostly about listening. If you just focus in on what the other person is saying, acting takes care of itself to quite a large extent.

Acting touches nerves you have absolutely no control over.

The point about a great story is that it's got a beginning, a middle and end.

You can act truthfully or you can lie. You can reveal things about yourself or you can hide. Therefore, the audience recognizes something about themselves or they don't -- You hope they don't leave the theatre thinking that was nice...now where's the cab?'