Three teenage girls are in a fashion designer’s studio in Hoxton, East London. One, Jenny, is appearing in a big Hollywood film with the New Teenage Sex God; the other two, her best friends Edie and Nonie, are trying not to tell her that her red-carpet dress will make her look like a cherry tomato. Eventually, Edie blurts this out. “And she’s the one who wants to be a diplomat,” says Nonie.

As many readers will know, Sophia Bennett’s debut novel Threads is the winner of this year’s Times/Chicken House prize for an unpublished children’s author (I was one of the judges). What you won’t know, until you read it, is that this is the most charming, funny, captivating new author to have come along since ... well, I don’t know when. Imagine Dodie Smith’s I Capture the Castle mixed with a dash of Louise Rennison, Meg Cabot and Audrey Hepburn’s Funny Face, but with something real that breaks your heart.

Nonie, the narrator, is mad about fashion but doesn’t have the figure for it — and doesn’t care. Her own taste in clothes sounds as hilariously bad as that of any 15-year-old, but her charm and kindliness make her the kind of person you would want as your best friend. Which is just as well, because when she meets Crow, a dyslexic black girl wearing blue cotton dungarees, an oversize pink tutu and a tattered pair of fairy wings, Nonie is about to get involved in a very different world. Crow is a refugee from war-torn Uganda who lives with her aunty, a cleaner. But she is also a fashion genius, and the story of how Nonie and her family realise this makes for a tale that should be part of every junior fashionista’s reading list.

Bennett’s confidence in her material is striking. She mixes real people — Simon Cowell, Karl Lagerfeld and Stella McCartney — with fashion names such as Louboutin, Dior and Swarovski, but instead of coming over as the usual dreary namechecking, the result is witty and affectionate. Perhaps the best thing is that when it begins you think you’re getting one kind of novel, all froth and fun, but then discover that you’re reading something that goes deeper. Yet Threads never depresses or lectures about the plight of refugees. Instead it persuades you that with love and friendship, lives can be saved.

Any child of 11+ who loves fashion and enjoys magazines such as Vogue or shows such as Ugly Betty will adore this, because it does for fashion what Ballet Shoes did for ballet. It’s a fairytale with wit and heart, and it shows the passion and hard work that go into success. You believe in Crow’s untutored genius and in the dresses she creates — one of which, naturally, will save Jenny from red-carpet humiliation. Serious Edie, sensitive Jenny and irrepressible Nonie are like the Three Graces, revolving around a child who is going to be saved by a fashion fairytale.

Disney, get out your chequebook. Threads is the next Princess Diaries — only hotter.

Threads (11+) by Sophia Bennett (Chicken House, £6.99; Buy this book; 272pp)

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