There must be a few, odd people — I am one — who missed the film Calendar Girls and did not realise it was inspired by a few women who have raised almost £2 million for cancer research since 1999. This astonishing achievement renders any criticism of Tim Firth’s stage version of Calendar Girls unkind and perhaps superfluous since this comedy of English manners enjoys more than £1.5 million of advance ticket-sales. Even so, since candour should be a critic’s’ constant companion, I need warn that though the show is in part very good, what a small part it proves.

Here, however, is a chance to enjoy displays of prudery, coyness and vulgarity, a mixed cocktail of character-traits that remains forever English. I am, of course, no lady, but then you need not be one to appreciate the long, lovely, first-act climax to Hamish McColl’s rather heavy-handed production. Yorkshire Dales’ ladies, variously young and old, fat and middle-aged, all from that haven of hyper-respectability, The Women’s Institute, are discovered revealing little naked bits of themselves for a camera, set up but not really flashed by Carl Prekopp’s photographer. Nothing unseemly, not even a serious glimpse of nipple, is allowed to sully the spectacle.

What makes the situation so amusing is that every photo is composed as a female mock-up of that all-male institution, a Pirelli calendar: fun is poked at men for whom gazing at prints of naked girls is the slow route to ecstasy. Each photo shows one woman in familiar institute situations but for the nudge-nudge of slight nudity. The girls are all helped into position, jettisoning clothes behind protective covering — the flesh of Siân Phillips’s well-preserved back flashes into view but ladies’ embarrassing parts are concealed beneath tasteful arrangements of fruit, tea-cups and kettles. The women pretend to dread having their mature or fleshy flesh made into calendar fodder. Only their raucuous leader, Lynda Bellingham’s no-nonsense Chris, remains qualm-free.

Notes of pathos are powerfully struck since the women are intent on raising a memorial fund for Gary Lilburn’s dying John, husband to Patricia Hodge’s fine, poignant Annie, who keeps her grief almost under wraps. The sunflowers that finally sprout on designer Robert Jones’s rather hideous set are in tribute to John. Yet you need watch Calendar Girls with critical faculties turned off. Far too much of it sprawls in an aimless comedy-free void. Just 25 minutes of it are divine.
Until 19 September (0844 482 5140)