Sophie and her novel

The latest literary work to come from the Dahl family may be a little closer to real life than its author is willing to admit.

Sophie Dahl, the granddaughter of children's author Roald, has finished her first book, The Man With The Dancing Eyes. And although she describes her 86-page novelette as "a fairytale for adults", friends say it mirrors the acrimonious end to her year-long affair with Mick Jagger.

Its launch on Valentine's Day next year is bound to cause the rock star - who is on tour with the Rolling Stones in the US - great discomfort. He is due to fly home for a family Christmas and doubtless will be embarrassed when details of the affair are dragged up.

One friend of the 25-year-old model said: "Sophie is calling the book fiction, but fiction is never really that - it's always based on life experience. The man with the dancing eyes is Mick, and writing the book has been a cathartic experience for Sophie. It's about how her heart was broken, how she healed and how she found love again."

Dahl is careful not to specify who the title character is based on - although she does hint at her on-off relationship with Jagger.

The book's heroine Pierre at first thinks she has found the perfect gentleman.

One passage reads: "Pierre and the man with the dancing eyes waltzed away into the night. Under the stars they sat with a picnic (cleverly conjured up by Claridge's), drinking oceans of champagne."

Pierre is left heartbroken after the man commits "an indiscretion that tore her apart". She flees to New York to recover. There's a percentage of experience and a percentage of fantasy," said the friend.

Dahl's agent Ed Victor is evasive. He told the Standard: "I think the book is probably based on her experiences of romantic love with several men. I mean, she's a 25-year-old woman and has had a number of lovers. If people want to say it's about Mick Jagger, that's what they'll say.

"Often in fiction, people use material from their own lives. And here - maybe she is, maybe she isn't."

Victor added: "The book is set mainly in New York. When the man breaks Pierre's heart, she goes to New York. Of course, Sophie lived in New York. It's very much a Breakfast At Tiffany's kind of feel about a young woman coping with New York. She never says how the character's heart is broken."

Victor said Dahl was already working on a much longer book. "There's a novel in the pipeline. She has all the tools necessary to become, in my view, a very good novelist."

When Dahl's relationship with Jagger ended, her grandmother, Oscarwinning actress Patricia Neal, told an interviewer: "I hope she stays away from the bastard. I've never met him, but that relationship was no good."

Perhaps the book is Dahl's way of rewriting history. She has said of the story: "It has all the elements of a fairytale, with a lovely, happy ending."