The Girls, Phoenix Theatre

Why? That's the abiding question that hangs over The Girls, the sluggish and entirely pro forma Tim Firth-Gary Barlow musical that goes where Firth's film and stage play of Calendar Girls have already led. Telling of a charitable impulse that succeeded beyond all expectations, the real-life scenario makes for heartening fare in our seemingly heartless times.

But the fact remains that this latest version of the narrative brings very little that is fresh to the table, unless you're so desperate for a new British musical at any cost that its mere existence is justification enough. 

As audiences by now surely must know, the "girls" in question (I guess it's too much for them to be referred to as women) are a community of Yorkshire folk who agree at the behest of amiable and persistent Chris (Claire Moore) to pose nude for a Women's Institute calendar, despite the mixture of physical, emotional, and moral alarm and chagrin that the prospect first elicits from our heroines. The worthy reason for Chris's lightbulb idea is so that money can be raised to buy a new settee for the hospital where the husband of her lifelong friend Annie (Joanna Riding) has just died. The gesture ended up taking off into the stratosphere and has netted in the region of £50 million to date. 

As tales of collective generosity go, this one is pretty hard to beat, though I'm not sure that it's so thematically inexhaustible that it benefits from being refracted through so many cultural prisms. (The TV mini-series is surely next, or maybe an ice ballet?) The structural difference this time is to save the actual calendar shoot for a climactic sequence of 11th-hour setpieces that boast at least six false endings before waving us goodbye with yet another of the life lessons in which the material cheerily traffics: "Never ever do what age expects of you." The lyrics to Barlow's score follow a similar fold: "There are coastlines in the heart / You won't reach if you don't start." And the (male) creatives know their musical theatre antecedents, not least when three husbands are seen to form their own de facto unit much like the middle-aged trio of guys who populate Mamma Mia! 

The reprise-heavy score couples the bubblegum pop sounds of Barlow's work on his recent Broadway musical Finding Neverland (rumoured to be London-bound) with various plaintive solos for Annie in particular –  the invaluable Riding (pictured right with James Gaddas as her husband) makes every moment of her centre-stage belting count – and a bustling first-act ensemble number, "Who Wants a Silent Night?", that, like much else on view, feels like padding. More is made here of the younger generation in ways that don't convince. Chris's teenage son Danny (Ben Hunter) is apparently so traumatised by his mum's risqué behaviour that the venture briefly risks being thwarted so as to maintain equilibrium back home. 

Before it gets given over to a bravura burst of sunflowers, Robert Jones's set piles high the kitchen cabinetry. This is a neat way of visualising the domestic contours of a show that goes against the grain of musical theatre grain in placing everday folk at its centre. Indeed, the piece wears its everyday homespun feel like some incipiently Brexit-era badge of honour. Annie sings twice about Tesco, while much is made of "England put[ting] Englishness on display" amidst a milieu where working abroad, we're told, is to have spent three months in Lancashire. 

The eventual disrobing comes with its own dramas and copious double entendres (breasts as "overhead lockers"), and one only wishes the wonderful Debbie Chazen, playing the vodka-swilling Ruth, weren't quite so demeaned by her particular portion of the shoot. The acting in general has a bracing conviction and artlessness that compels attention, whether Claire Machin is zinging a phrase like "bun-toucher" across the footlights or Riding and the ever-zestful Claire Moore are communicating a depth of feeling and rapport that doesn't need over-elaboration by the script. 

And watching The Girls in the very playhouse that was home for so many years to another quintessentially British chronicle of life on the emotional frontline –  namely, Blood Brothers – made me realise anew the gap that does exist in the market for musicals that reflect playgoers' lives back at them. It's too early to tell whether this show will enjoy the longevity of its Willy Russell predecessor but if it does, the cream puff industry along Charing Cross Road is going to be in business for some time to come. 

• The Girls at the Phoenix Theatre until 15 July 
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