STARRING in a swashbuckling Hollywood film is many a schoolboy’s dream. For Ed Speleers, from Chichester, that dream has come true.

At the age of 17, his acting experience confined to amateur school productions, he found himself cast as the hero of Eragon, an epic fantasy adventure to be released this year.

Ed was among tens of thousands of teenagers to be auditioned during a worldwide search by Twentieth Century Fox. His co-stars are some of the industry’s biggest names, including Jeremy Irons, Robert Carlyle and John Malkovich.

Ed, now 18, told The Times yesterday: “I have to pinch myself every morning to make sure I’m not dreaming.” The film, which is to be released on December 15, is an ambitious adaptation of the sword-and-sorcery novel by the American writer Christopher Paolini which became a publishing sensation in 2003.

The book sold more than one million copies in six months and spent 87 consecutive weeks on the New York Times children’s books bestsellers list. When it came out in paperback earlier this year, it again shot to the top of the charts. It has now been published in 37 countries.

In Britain it has topped the Sunday Times children’s charts. A special edition will be issued to tie in with the release of the film. Inspired by Teutonic, Scandinavian and Old Norse legends, as well as myths from the British Isles, it tells the story of a 16-year-old boy and a telepathic dragon who set out to defeat an evil king.

Ed had wanted to act since he was 12, having caught the acting bug when he played Puck in a school production of A Midsummer Night’s Dream.

It was when he was preparing to play Hamlet on the school stage at Eastbourne College that a teacher recommended that he have a go at auditioning for the film. He turned up, read some lines and found himself being called back.

“Next thing I knew,” he said, “I was signing up for a movie. LA phoned my Dad, who told me, ‘You’ve got the part’ . . . I started yelling and screaming.” As the son of a financial consultant and a former naval nurse without connections to the film world, Ed had not had particularly high hopes of being cast. He had not even told his friends about the audition. “I’d heard so many stories about how ‘it’s not what you know but who you know’ in the industry,” Ed said.

As the shoot would be long — seven weeks at Pinewood Studios, as well as four months in Hungary and Slovakia and a month in Vancouver — he decided to drop out of his A levels.

He said: “I would have been a fool not to do it. Opportunities like this don’t come twice.”

With an acting coach guiding him three weeks before the shoot, as well as on set, he also learnt swordfighting, horseriding and fight sequences. He discovered how to act with a 12ft (3.7m) pole topped by a tennis ball as a stand-in for the dragon to be created later with special effects. He has only just seen the screen creature, in a trailer for the film. “It looks amazing, very believable.”

Whether Ed completes his schooling and goes on to university, as his parents had planned, remains to be seen: he wants to pursue a career as an actor. “I don’t want to be a stockbroker,” he said.

Stefen Fangmeier, director of the film said: “Initially we were looking at older actors to play the role and then we had a change of heart. So we rushed out to look for kids of Ed’s age.

“Ed was the first one that morning and I just got a sense of his sparkle, of his life. It was the kind of thing where you know he could be a movie star. I could see he was a natural.”