Mamma Mia! is this summer's second film to be not just critic-proof, but quality-proof. Just as Sex and the City didn't even have to pretend to be a film to send a million stiletto heels clacking towards the multiplex, so this filming of the ABBA musical is bound to have the coachloads who saw the stage show pulling up outside the Odeon. Given that no effort has had to be made (nor has been made) to convert theatrical extravaganza into summer hit, the question is: just how bad is Mamma Mia!? As bad as Sex and the City? Amazingly so, yes (and it's shorter). The worst film of the year? Maybe so, because its badness is so much louder than everything else around. It is offensively awful, howlingly woeful, naff beyond belief. This is a film so bad that when Pierce Brosnan launches into his rendition of "S.O.S." - I use rendition in the same sense as the Bush administration - it is, in context, no worse than any other element thereabouts. It's The Da Vinci Code with songs. It's that bad.
The story, for those who really need it, unfolds around a sundappled Greek island. Sophie (Amanda Seyfried), a young woman on the eve of her wedding, is determined to track down her real father to accompany her down the aisle. To this end, she invites three of the best placed candidates to the hotel she shares with her mother (Meryl Streep). From Sweden, there is roguish sailor Stellan Skarsgård (!); from the US, hunky architect (zzzzz...) Pierce Brosnan; and from the UK, there is the very Colin Firth-like Colin Firth (St. Trinian's and this in the same 12 months: someone needs a new agent). Each gets an opportunity to plead their case for paternity, that is when they're not being drowned out by one of their fellow cast members caterwauling "Money Money Money", "Gimme Gimme Gimme" or "I Do, I Do, I Do, I Do, I Do".
One cinematic precedent here would be last year's film of the stage musical Hairspray, which turned something from John Waters' self-described vulgar imagination into winning pop. Mamma Mia!, however, goes the other way, using winning pop music as a pretext for the worst kind of vulgarity: blocked toilets, fake tans, divorce-flaunting, randy bartenders, Julie Fucking Walters, TV commercials for Maltesers that are secret trailers for the film (a particularly insidious development), and the singing of a key line in the title number as "just how much I missed ya" rather than "you" - even native Swedish speakers Anni-Frid and Agnetha managed better than that. This vulgarity feeds into (but doesn't excuse) the shoddy filmmaking: the endless clumsy close-ups, the cheap blue-screen backdrops surrounding the villa. And did director Phyllida Lloyd not consider hiring performers who could actually hold a tune?
Of course, we're not meant to be thinking about such things (or thinking about anything), rather sharing in the tremendous fun this cast had being paid to spend two months in the Med. Depending on personal taste, the film will mark either the apex or the nadir of Streep's recent loosening-up: not only does she get to smile and laugh (as she wasn't allowed to between 1978 and 2002), this time, she's given the opportunity to belt out a couple of numbers while wearing dungarees - enough, I'm afraid, to leave me hankering for the old Streep whose daughter was eaten by dingoes. Seyfried, a quirkily appealing presence in films both good (Mean Girls) and bad (Alpha Dog), submits to the general air of wide-eyed, sunkissed blandness; and surely the producers could have done better, in hiring a young male lead to meet the demands of the teenage-girl demographic, than The Escapist inmate Dominic Cooper, whose shifty demeanour and vulpine features suggest his character may well have several body parts in the boot of his Fiat Punto. As for Walters' climactic performance of "Take a Chance on Me": well, celibacy has never seemed more appealing.
The biggest crime Lloyd's film commits - bigger than those it commits against the cinema, good taste, and the paying public - is that it commits against the music that inspired it all. ABBA have always enjoyed a following conscious of the campy-kitschy aspects of their output, but these singles could equally be reclaimed as perfectly crafted three-minute bulletins on the human condition, conveying therein a real sense of joy, loss, heartbreak and abandonment, only a shallow idea of which Mamma Mia! appears to be interested in. (Dare one suggest "The Winner Takes It All" gains not very much in profundity by having Streep wail it at Brosnan in front of a Greek sunset?) Musically, the film comes in somewhere between Moulin Rouge! - which similarly trashed half-a-dozen great pop songs - and the state-sanctioned Great Democratisation of Pop overseen by Chairman Cowell, persuading us that anyone can have a bash, no matter their talents, and so long as someone somewhere stands to make a great deal of money from it. These arrangements smack of those Top of the Pops compilation albums from the 1970s, where the hits were sung (quite poorly) by session singers; camp means never having to admit something's no good.
This is, one suspects, part of the Mamma Mia! experience's appeal: that it should have the recognisable ring of hen-party karaoke, or of something sung into a hairbrush in front of the mirror. On the big screen, however, it just looks like the latest gross reduction of our already falling cultural standards: something intolerably sloppy, hastily repackaged as the feelgood film of the summer. The sad sight of the four ABBA bandmates reuniting for the non-event of the film's Stockholm premiere is topped only by the sight of Benny and Bjorn's cameos in the film itself. To them, I offer my congratulations: in return for a handful of gold coins, they have ensured their music can never again be encountered without the attendant dual whiffs of ordure and fromage. To everyone else, I can only provide the following stark warning: every penny you hand over at the box office for Mamma Mia! will only bring us closer to the movie version of Our House starring Danny Dyer, or of the Queen musical We Will Rock You, starring Russell Brand and Justin Hawkins from The Darkness.
Mamma Mia! is available on DVD through Universal Pictures; a sing-along version screens on ITV2 today at 4.20pm, ahead of the sequel, Mamma Mia! Here We Go Again, which opens in cinemas nationwide this Friday. God help us all.