Filming for The Golden Compass, the movie adaptation of Oxford author Philip Pullman's Northern Lights novel is well under way, with some scenes completed in Oxford.

The film has had a chequered history pre-production with three directors and two screenwriters, but received a massive boost earlier this year when Oscar-winning actress Nicole Kidman agreed to play the part of Mrs Coulter.

Yesterday, New Line Cinema, which is making the film, released the first still from the movie, which shows Miss Kidman talking to Dakota Blue Richards, the previously unknown 12-year-old Sussex girl chosen to play Lyra Belacqua.

Nicole Kidman was Mr Pullman's first choice for the role, and he has backed New Line Cinema's efforts to capture his story on the big screen.

The author, who lives in Cumnor, has attended the filming of some scenes in Oxford, and further shooting is taking place at Shepperton Studios near London.

Mr Pullman said: "I put my trust in New Line Cinema, not because of their unrivalled expertise with computer-generated imagery, but because the conversations I had with everyone involved led me to believe that they shared my understanding of the democratic nature of reading, and shared my faith in the free play of the human imagination."

In March, open auditions in Oxford for the lead role of Lyra attracted more than 3,000 girls.

Would-be stars were told they needed no previous acting experience, as the production company was looking for a down-to-earth girl aged between nine and 13.

Mr Pullman stayed away, as he feared his presence would be intimidating.

Auditions were also held in the Lake District and in Cambridge, where Dakota Blue Richards was discovered.

The Golden Compass follows Lyra, who lives in Jordan College, Oxford, as she uncovers a plot against her uncle, Lord Asriel.

Soon she is in over her head as she discovers a whole new world of possibilities, at the centre of which is the glamorous Mrs Coulter.

Mr Pullman's final instalment of the trilogy, The Amber Spyglass, was the first children's book to win the Whitbread Prize. The trilogy has sold nine million copies worldwide.

The writer has pledged to write a fourth book, a prequel to the trilogy, featuring the same characters.