Bridget Jones's little diary has leaped to the big screen at a star-studded premiere in London's West End.  The film's stars—Renee Zellweger, Hugh Grant and Colin Firth—were all there on Wednesday, as was Helen Fielding, who first dreamed up the character of the neurotic Bridget.

Geri Halliwell turned heads at the premiere of Bridget Jones's Diary with a daring backless dress. Halliwell arrived in a backless, one shoulder Julien MacDonald creation and wandered around greeting fans outside the Empire cinema before handing over a spare ticket. Inside the cinema, Halliwell—who provides the song It's Raining Men for the soundtrack—embraced Zellweger and  handed over a handmade bracelet. The actress looked delighted with the beaded bangle, which she showed off and was inscribed with the words "so hip it hurts".
 

Zellweger also won admiring glances as she showed off how she had regained her figure after losing the 20lbs she gained for the film in a revealing black crocheted dress.

Renee Zellweger and Hugh Grant, Dominic West, Alan Cumming, Frances McDormand, Donald Trump, Tara Fitzgerald, the singer Moby and the veteran television star, Barbara Walters, were among the British and American celebrities who gathered at the Zeigfield Theatre in New York on Monday night to celebrate the premiere of Bridget Jones’s Diary. Miss Zellweger, the American actress who was granted the role of the famous British singleton, only after she agreed to put on 20lbs, stunned the audience not only with her impeccable London accent, but also with her dramatic weight loss.

Now skinny as a starling’s rib, and wearing a tiny black suit by the New York designer Marc Jacobs, it was clear she had lost at least a stone more than she had put on, giving Calista Flockhart, the tiny star of Ally McBeal, a run for her money as America’s most anorexic actress.

“I miss London, I really do, I really do! I miss the Met Bar,” she said, adding that working incognito for an English publishing company as part of her research for the role, and then making the film with Mr Grant and their co-star, Colin Firth, was a wonderful experience.

“It was unique, extraordinary, every day brought new opportunities,” she said.

Mr Firth was unable to attend because his wife is expecting a baby this week. Sporting a spikey new haircut, Mr Grant seemed peevish and refused to speak to the British press. Asked briefly if he enjoyed playing the bad guy as a change from his recent role in Notting Hill, he snapped: “I’ve played the bad guy before you know. It was a welcome return.”

The film was co-written by Helen Fielding, Bridget Jones’ creator, who arrived at the theatre with her American boyfriend Kevin Curran, a writer for The Simpsons. Asked if he had managed to woo the real-life Bridget Jones, he said sheepishly: “I guess you could say that, she’s a wonderful woman.”

The two now live together in Los Angeles. Ms Fielding, who was dressed in a blue suit by the British designer Ghost, and wearing a diamond necklace by Asprey, said it was important to her that Ms Zellweger had been prepared to put on weight for the part.

Another co-writer was Richard Curtis, creator of the Black Adder series and Four Weddings and a Funeral. He said he was relieved he had not had to disinfect his feet before arriving in the United States, but he was worried about not being able to take food back to London with him. Looking forward to further projects, he added he was thinking of creating a new Black Adder series with Rowan Atkinson playing a college professor who hates students.

Eric Fellner, one of the film’s producers from the British company Working Title, pointed out that if the film is a reasonable success it will mean Mr Curtis’ last four films, which include the blockbuster Notting Hill, will have a combined gross of more than $1 billion.

The film was directed by Sharon Maguire, a BBC documentary maker who was the real-life inspiration behind Shazza, Bridget’s best friend. Ms Fielding always promised that if the book was ever made into a film, then her friend would direct it. The movie also includes several cameos of Ms Fielding’s friends including the authors Salman Rushdie, Julian Barnes and Sebastian Faulkes. Lord Archer also makes a brief if unflattering appearance.

After the screening Barbara Walters, a famous singleton herself, said she loved the film. “Renee was adorable,” she said.

“I shall give it a good review,” said Jonathan Foreman, film critic for the New York Post. He added that he liked Mr Curtis’ eye for social detail though he feared an American audience might miss the subtlety. “My only worry is that the film has such a thick heroine. No American film would dare to insult its target audience like that.”