Did your young son have any influence over your decision to play Hagrid?

He made it quite clear that if I didn't play the role, I would be dead within a week. As you can imagine, the guy who turned down Hagrid would be like the guy who called the Beatles a guitar band. So I couldn't possibly refuse, really.

How do you cope with the weight of expectation on the film?

I got a letter from this woman just before we started filming, and she said: "I'm really glad you're playing Hagrid, because the expectations of millions upon millions of children throughout the world will be resting upon your shoulders." So no pressure then! It's like driving a car. If you get in and think, If I turn the wheel now we'll all die, you'd never drive a car. You just give it your best shot. I think that's true of everybody in the film. Everyone was aware how important it was and what a big responsibility it was.

Is filming still a nerve-wracking experience for you?

I've been in this business for over 20 years, and it still scares the bejesus out of me walking onto a set for the first time. There's at least a 100 people you've never met before, and you think, This [scene] cost £5 million, I'd better get it right.

JK Rowling was very keen on you playing Hagrid. How did that make you feel?

I was terribly flattered, because by then I was a huge fan of the books. I always really liked Hagrid. I thought Hagrid was an interesting guy, he drives a motorcycle, and has his own place in the country.

You're going to be idolized by children all over the world after this. How are you going to react?

I'll have to cut down on being pictured staggering out of a nightclub at three in the morning. It is a bit of responsibility, I suppose, but I shall take it lightly.

"Harry Potter and the Philosopher's Stone" is released in UK cinemas on Friday 16th November 2001.

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