'On every take we did, I cried'

"When the script first came to me, it was very, very long, about four-and-a-half hours. Alan Bennett, who'd written it, had used about eight different typewriters and the o's were up there, the a's were down there,and the t's were everywhere. When he got a little bit that he thought he liked, he would snip it out of the page and build up a sort of collage. And then they were put into the photocopier and we got these pages of strange happenings.

Nick (Nicholas) Hytner, the director, decided to give a reading of the play. So all these people came along; it was very nervewracking, and I was the only one who was cast. I just put all my energy into it. I didn't know what I was doing. I'd turn the page and go, Pop!: whatever came to me, I did. It was very unsculptured, but it's the way I like to work, and it infuriates most people who have to work with it, including directors.

That first day Alan Bennett, who thought he'd written a play - almost a satire - about the medical and the political factions in the 18th century set against this mad King, suddenly realised he'd written a human document about the King. And that was just from the reading.

We had a bare stage: I asked Nick if I could have some clothes - just a dressing-gown, and a pair of slippers, a hat or a cloak - and right from the very first rehearsal it was this that started to shape what we were doing and also to catalogue the illness that the King had.

On research

When I've played real-life people such as Pierre Curie or C.S. Lewis in Shadowlands, I do a lot of research about the period and the people, and then discard it, and play the play. Play the script. It's a very good tip and one I learnt the hard way, and one which I now do.

Rehearsal

We rehearsed for George quite a lot. I think Nick knew at a very early stage that the best thing with me was to just let me go, and the more he let me go, the more I would come to terms with the role. In fact, I was told much later that the members of the company had decided that they might organise a T-shirt, and on it was written "Nick, I've got an idea!", because apparently I used to say that every day.

Switching gears: acting for the film version of King George

It's always very difficult, the most difficult thing, to translate from one medium to another. I think all you can do is wash your brain. I'd never met Helen Mirren. I loved working with her, and she was wonderfully helpful, because it was my first leading role in the movies. She said to me one day - because I was worrying about a scene - 'Do something, then let go, get on to the next, because the next is more important'. She was great fun, and naughty, all those things. She's good news.

Charting a role

You start off with the King perfectly all right. But then, somebody who knew him would think there's something odd about him, he does something unusual (makes stammering and harrumphing sounds), or some trick of the voice. And you start introducing these inconsistencies, and gradually build to a state where he gets up at four in the morning and wakes up all the pages and then starts to talk filth and rubbish. Alan Bennett said to me once: 'Oh, just say whatever you want to say', and I said, 'Alan, I can't, you've got to give me lines.' He then went to an expert on madness and found how they harped on certain words, and kept returning to them, almost like a Lewis Carroll fantasy world.

The most touching moment for me is when Helen is running across the grass at Windsor Castle, and it's snowed, and the King has been put in a straitjacket and thrown into the royal coach, and as the coach goes past, he looks back at her, she looks at him, and this man is wrenched away from his home and his family, and you don't know where he's being taken.

I remember one instance in the film of King George when Ian Holm opens the door, and the restraining chair is in front of the King. For some reason, it really upset me to see that chair, and my eyes filled with tears just at the rehearsal, and every take we did, I cried. I just knew how the King must have felt, being confronted by that, with those goons around that appalling instrument of abuse. It used to upset me, and I can't watch the film without being moved by that moment.

Academy Award nomination:

Best Actor

The news that I'd been nominated was totally unexpected. I was at a memorial service at the National Theatre for an electrician and someone came up and said: 'Hey! You've been nominated for an Oscar!'.

When we went to Los Angeles, I suddenly realised that it was an American celebration and I felt a real foreigner. It was most odd; it was almost as though I'd come to the wrong party. I'm a huge star spotter and I was talking to people such as John Travolta and Jodie Foster. That was the most exciting part, seeing all these people really close up, and peeing next to them in the lavatory. Steve Martin was in the next cubicle to me.

Asking the director for help

There are very many cases - in fact, most cases - where I'm on the wrong track, and I have to be put right. The sort of directors that I work best with are those who don't try to pin me down, who don't say 'Yesterday you did it like that, and I like that way', because that hems me in. Directors either steer clear of me, or they go along with it.

I was doing a Chekhov play once, and the director rang me and said: 'I'm calling you to tell you to stop interfering! You keep telling the actors to do things I don't want them to know for another three weeks', and I said 'Why? Why don't you want them to know?' She said 'That's my business: I'm the director.'

I'm not really that technically adept, you know. I have a very good instinct, and I'm very lucky about that. It sometimes lets me down like everybody's does. But generally speaking, I know what's right, and I have a certain amount of taste: 'No, that feels wrong, I don't think I'll do that', and then I'll start to change things. In the course of a play I'll totally change my performance, every night, totally. Moves, everything, which always angers a number of my colleagues.

I had a terrible row with this English actress. She said 'I think you change things just for the sake of changing them', and I said 'Yes, of course I do'. She said the art of acting is to be able to come into the theatre every night and give exactly the same performance that you gave the previous night.

Surely the important thing is to keep it fresh. Once you've left the rehearsal it's out of the director's hands, it's in your hands as a group to maintain the thrill, the danger, the spontaneity. You make it a happening every night and you get people who don't agree with the way you're doing it.

The Hollywood megafilm experience: Demolition Man

I did Demolition Man because I wanted to do the screen version of King George, but I had no credibility. I always thought Tony Hopkins would get the part because he got the role I originated on stage in Shadowlands. Joel Silver, who was the producer, saw The Madness of George III, the play, and called up my agent, and said 'I WANT HIM! GET HIM!' So I thought, well, maybe if I did this movie, there would be a chance of playing the King, because they were talking about the film at the time."