Theatre: Thank you for the musical

MAMMA MIA! PRINCE EDWARD THEATRE LONDON

MY FAVOURITE moment in Mamma Mia! - the ridiculously enjoyable new Abba Greatest Hits-style musical - comes at a point when one of the group's biggest hits is ingeniously twisted to suit two expansively gay characters who embark on a beautiful friendship whilst out cottaging. It's certainly singalong time with a difference when the couple let out a defiant chorus of "Portaloo - wouldn't escape if they told us to/Portaloo - oh, oh, oh, oh..."

All right, only kidding. In fact, Abba's Eurovision winner is just about the only golden oldie they don't manage to shoehorn into the show. By the standards, though, of these K-Tel-compilation West End musicals, Catherine Johnson's book does a pretty nifty integration job. Decked out with jokes that make Are You Being Served? sound like Moliere, the original plot involves a young girl on the verge of marriage, and her relationship with her mother when she discovers that anyone of a trio of men could be her father. Inviting them all to the wedding, she tries to distinguish which of them should give her away.

The real drama, however, is less between the characters on stage than between the audience of fans and the music. A firmly camp note is struck from the opening announcement that "we'd like to warn people of a nervous disposition that platform boots and white lycra will be worn in this production". The show proceeds as though the fans have generously donated the songs for the evening (opportunities for a ditty are then engineered with a blithe outrageousness that is more Crackerjack than Carmen) and roars of proprietorial delight greet each cheeky intro.

It's certainly handy that the prospective bride's mother (the excellent Siobhan McCarthy) used to front a Seventies female rock band and that she's invited to the wedding her old backing singers: Louise Plowright's leggy, comic broad and Jenny Galloway's very funny mini-mountain who really has the measure of the show's idiom. No excuse, then, not to break into an "impromptu" rendition of "Dancing Queen", replete with hairdryers, vibrators, and roll-on deodorants as mikes, designed to bring out the dancing queen in the straightest soul.

Indeed, the most avid collector of kitschy cues for a song might find himself a overwhelmed as the two friends comfort the mother with the mock- soulful solace of "Chiquitita" or as one of the possible fathers unwraps Alan Partridge's Pringle sweater to "Knowing Me, Knowing You" and solemnly warns the bride of the pains of divorce.

The expatriate Greek island setting allows for campy (and badly done) underwater dream sequences. But there are also moments of heartfelt feeling, as when Ms McCarthy helps the daughter dress for the nuptials and sings, in pulsing voice "Slipping Through My Fingers", a spangly, plangent lament for the way our children elude us and then leave us for good. It's also the moment when the intriguing generational aspect of the plot comes into focus.

Phyllida Lloyd's handsome production provides a terrific mood of airborne silliness. Abba is pop's most famous palindrome and, whichever way you read it, Mamma Mia! looks like being a hit.

To 11 Sep (0171-447 5400). A version of this review appeared in later editions of yesterday's newspaper