On paper, Fat Friends the Musical ticks all the boxes: a nostalgic revival of a much-loved TV series, written by the show’s original creator Kay Mellor; a heart-warming story about loving yourself and your body no matter what you weigh; and a starry cast featuring stage and screen favourites that include Jodie Prenger, Sam Bailey and Kevin Kennedy.

The show condenses some of the main plotlines from the first series of Fat Friends into one story, primarily focused on Kelly (Jodie Prenger), who’s about to marry the love of her life, Kevin (Joel Montague), and would be the happiest woman in the world if only she could fit into her dream wedding dress. But that’s not so easy when your parents (Sam Bailey and Kevin Kennedy) own a fish and chip shop, your skinny sister (Rachael Wooding) won’t stop teasing you about your weight, and you’re hungry all the time. Encouraged – for different reasons – by best friend Lauren (Natalie Anderson) and dieting queen Julia Fleshman (Natasha Hamilton), Kelly sets out to lose those extra pounds… but will being slimmer actually make her happy?

It’s great to see Kelly, Betty and co again, thirteen years after Fat Friends left our screens, and the show’s script sparkles with Kay Mellor’s trademark Yorkshire wit and warmth. Just as we remember them, the characters are loveable and easy for real people to relate to; some of the biggest laughs are ones of recognition as the slimmers shed as much clothing as possible before their weigh-in, or battle with themselves over whether or not to have that bag of chips. We’ve all been there, and that’s why it works. (And if you don’t leave the theatre craving fish and chips, you’re a lot stronger than I am.)

Jodie Prenger is well cast as the irrepressible Kelly, and soon has us on side with her down to earth humour and unflinching honesty. Sam Bailey – just a couple of years older in real life – seems an unlikely choice to play her mother, but the two pull off a convincing on-stage relationship, with shy, nervous Betty the very opposite of her outgoing daughter. Meanwhile, Rachael Wooding doubles up so effectively as Kelly’s sister Joanne and Julia’s downtrodden assistant Pippa that I didn’t even realise it was the same person, and Natalie Anderson throws herself with seemingly limitless energy into her one character Lauren’s multiple roles as dress shop owner, slimming class leader and Zumba instructor (not to mention hopeless romantic).

Unfortunately, the music – composed by Nick Lloyd Webber, with lyrics by Mellor – doesn’t quite match up to the rest of the evening. Despite a few stand-out numbers, and the undeniable vocal talents of Sam Bailey, Jodie Prenger, Natalie Anderson and others, the songs on the whole add little to the plot and, though well performed, are not particularly memorable. Given that its strength lies in the characters, story and dialogue, you have to wonder if the show, which runs at over two and a half hours, might not have worked better as a play.

Although as a musical it doesn’t quite work for me, Fat Friends is still a good night out, with a talented cast and a strong message about body image. By updating the story to the present day, Mellor is also able to cover both the opportunities and the dangers posed by social media, and the many ways in which we allow others – both people we know and complete strangers – to dictate how we should feel about ourselves. A feel-good show with a heart as big as its appetite, this revival of a TV favourite is a lot of fun for old and new friends, of all shapes and sizes.