Oscar winning actor Jeremy Irons wanted to join the circus before he decided to seek a career on the stage.

As his latest film, the dragon fantasy Eragon, opens he talks to Steve Pratt about how he reconciled in 'boring' middle class background with his chosen profession.

Anyone who believes they can embarrass a serious actor like Jeremy Irons by mentioning early TV appearances prancing around being jolly on BBC children's show Play Away should think again. The Oscar-winner always looks on the positive side no matter what he's doing - or how ridiculous he might look now in childish Play Away mode.

"There's a positive from everything, even the terrible movies one falls into sometimes," he says, relaxing in a London hotel room on the day his latest movie, the fantasy adventure Eragon, had its world premiere.

"I often think there's positives from failure more than success. But Play Away was great because it enabled me to sing and to lark about. And it's re-run whenever anybody wants a cheap bit of television, but that's the nature of it.

"Even Jack Nicholson has the dentist, or whatever it is he played. They keep showing that. At least I wasn't posing naked in some magazine, which is the other thing that some people have to worry about."

Irons in person confounds expectations. You anticipate someone a bit aloof or precious, a legacy of the roles with which he's most associated. That's why Play Away seems so out of character for someone described in one film reference book as "British leading man of the introspective type".

Even stranger is learning that joining the circus was a career possibility he considered. That fitted in with the reason he wanted to become an actor in the first place. "The desire to be a gipsy, to not have to toe the line and play by the rules. I seriously thought about the circus, or the fairground, or the theatre," he recalls.

"I remember wandering around the circuit of the fairground at Epsom Downs before Derby Day - because I was busking in a pub on the corner of the Downs - and I saw the accommodation, which was a sort of store with four bunks in it, and I thought I couldn't cope with that for long. I wanted a bit more than that."

Instead, he answered an advertisement on the back of The Stage, the entertainment industry newspaper, and got a job in the theatre at Canterbury. It proved the right choice. "I liked the life, especially the nocturnal aspect of the life - loved the smells, loved the people. So I thought I wanted to go to drama school and learn how to do it," he says.

The longing for an exciting, unorthodox job was at odds with what he's called his boring, middle class background. He says that, having tried to get his elder brother into the type of career he thought he should be in, his father was overjoyed when young Jeremy went to him with an idea of what he wanted to do.

"He didn't give it much hope. He said it seemed to be a pretty rocky profession, and it was quite difficult to hold relationships together and things. But he said, 'I'll help you because it you don't try it, you'll never know and you'll always resent me for not supporting you'.

"So he did, and he paid my fees through drama school. I had to work for money for the holidays."

His father died shortly after he'd made Brideshead Revisited and was making The French Lieutenant's Woman, so "he sort of knew I was on the way and that his faith had been well placed".

He hadn't expected to work in movies, but after being on stage in Bristol for three years came to London wanting a film or the West End. "Simon Ward was playing all the roles that I would have been right for, such as Young Winston," he recalls.

"Nijinksy was the first movie I made because Nora Kaye, who was married to Herbert Ross who made the film, had been a pupil of Mikhail Fokine, whom I played, and thought I looked very like him.

"Then for The French Lieutenant's Woman, I was quite good casting for my look. They didn't need a star because they had Meryl Streep. So that's how I got my chance. I didn't expect to work in movies."

His performance in ITV's Brideshead Revisited brought him international recognition and awards, including a Golden Globe for best actor. He also has an Oscar for his portrayal of Claus von Bulow in the film, Reversal Of Fortune, and took home an Emmy this year as the Earl of Leicester in Elizabeth I on TV. Clearly, he's proved himself on stage and screen, both big and small.

In Eragon, a fantasy adventure based on Christopher Paolini's bestselling book, he plays mentor to the dragon-riding teenage hero battling the forces of evil. It would've been understandable if he'd turned down the role as his previous brush with a dragon movie, Dungeons And Dragons, was not a success.

"I always worry about first time directors but you have to risk things and I thought this had been better managed from what I could see than the first movie," he says.

The role also gave him the chance to saddle up again. On the historical epic Kingdom Of Heaven, director Ridley Scott had to keep telling Irons he wasn't needed as they had a double to do the riding.

He loved the riding on Eragon. "I could spend all day on a horse and be very happy," he admits. "I was less interested in the fighting and the practising and all that. You know, a big movie is very cumbersome. It takes a long time, so it went on a little bit longer than I'd expected."

There were no worries about being shown up by the younger 18-year-old actor, Ed Speleers, playing the teenage hero. "He was much quicker because you're quicker when you're young. You remember. I kept forgetting the sequence and halfway through I'd say 'let's stop and work through that again'. But it takes longer to learn. I think your brain cells die, don't they?"

Irons recently returned to the London stage in Embers, which wasn't so much like recharging his batteries as draining them. "It was exhausting. But it did everything that I wanted it to do in that it got the muscles going again and got me in touch with the audience," he says.

"It was very interesting because it was a new play and I wanted to see if it would work. It worked all right, not perfect, but all right. At my age you have to always be looking for interesting roles because it's harder to find them in movies.

"Guesting, as I do in Eragon, is not particularly satisfying. It's lovely to be in control of a play or a film, as I used to be. So I think I'll keep going back to the theatre if I can find the work."

Eragon (PG) is now showing in cinemas.