The sunny, funny world of musical comedy: Stephen McGann and Gemma Craven in 'Calamity Jane' Photograph: Ian Tilton
The 1953 film Calamity Jane was a shameless attempt to cash in on Annie Get Your Gun. It failed, but the rough-and-tumble image of tousle- haired, trigger-happy Doris Day endures. Undeterred, the gutsy-voiced Gemma Craven jumps into her fringed deerskin with scarcely a look over her shoulder, bursting on to the screen aboard a stagecoach belting out the opening number, "The Deadwood Stage". Minutes later, she is trading insults with Stephen McGann in the feisty duet "I Can Do Without You". He's less of a case of Wild than Mild Bill Hickok, but no matter. She's got more than enough energy for the pair of them and that's what counts.

Calamity heads off to the windy city to bring back actress and Deadwood pin-up Adelaide Adams, first seen looking like a cross between Marie Antoinette and Lily Savage. When she mistakenly returns with Adams's maid Katie, guns start going off and our heroine winds up learning a thing or three about being a girl. Craven even scores over Day at her moment of revelation about the man she loves, singing the hit "Secret Love". She hasn't got Day's silken tone but she doesn't have to compete with the film's dreadful Vaseline-on-the-lens fantasy sequence. Although no miracle of structure, the show is built around company set pieces and David Needham's exuberant musical staging carries all before it. When the cowboys and Deadwood locals aren't strapping their thumbs beneath their braces and kicking up their heels, they're singing their heads off, throwing saloon girls over their shoulders or tapping their way to a first act curtain as if their lives depended on it.

The 1980s "more sets please, we're British" ethic (just sit back and applaud the budget) turned the musical into spectacle, but this is an exception. The backstage crew must be moving as fast as the dancers thanks to Paul Farnsworth's designs, which run to enough cloths, trucks, flats, furniture and flying pieces to fill an aircraft hangar, let alone the tiny Sadler's Wells stage, but everything enhances and enlivens the materials. When Calamity and Katie sing the now laughably sexist "A Woman's Tough" - "A woman and a whisk broom / can accomplish so darned much" - Farnsworth's comic tricks turns Calamity's drab cabin into gingham heaven, complete with freshly-shot pigeon pie. He also gets more good gags out of mechanical horses than anyone has a right to.

When Nicholas Hytner won an Olivier for Carousel, they remarked that all he did was direct the sub-text. With Calamity Jane, going for underlying truth is a waste of time. Paul Kerryson's production could handle a generous injection of irony, but he knows that the piece exists in the sunny, funny world of musical comedy. Looking at some of the more po-faced products in town, this show may be old-fashioned and downright daft but it sure is welcome.

To 15 June. Booking: 0171-713 6000. Then touring