FILM / Hi honey I'm homicidal: Adam Mars-Jones on ironic tastelessness posing as suburban warfare in John Waters' latest black comedy, Serial Mom

There's no more fragile hold on a movie audience than shock value - it can work for a single film, but it's tricky to parlay that into an entire career. You depend on people wanting to see what they don't want to see, and any potential cult following will be eroded from one side by disgust and from the other by jadedness. All things considered, John Waters has had a pretty good run for his money. When his film Polyester was accompanied by the gimmick of Odorama - scratch-and-sniff cards that you were supposed to activate at set moments to release a more or less gross aroma - most audiences did so, with groans of meek protest, as if they had no choice in the matter. They submitted willingly enough to the tyranny of Waters' tastelessness.

With Hairspray, Waters showed signs of mutating into something more ordinary but also more durable. The story was set in 1962 (when Waters was in his teens) and was affectionate about that period, when a crucial decade was getting off to a slow start. There was a social and even a political theme - the need for racial integration - lightly handled. There was one established star, Divine, and a new one, Ricki Lake as the heroine, apparently ready to pick up Divine's ambiguous torch and carry it into the Nineties. But since then, with Cry-Baby and now Serial Mom, Waters has got stranded. His films are no longer obliged to be tatty by budgetry necessity, but having more money to spend hasn't noticeably enriched his imagination. Gleeful tastelessness has been usurped by an ironic tastefulness that doesn't have a lot of energy to it.

After so many films, subversion of conventional narrative can look rather like inability to tell a story. Star casting begins to show up inadequacies in other areas. If you can afford to hire Kathleen Turner for her presence and her acting, it looks like false economy not to hire comparable talent for scriptwriting or direction. When John Waters was a one-man band, the description writer-director was a flag of convenience rather than an existential decoration. As time goes by, the distinctiveness of his talent in either area is becoming a doubtful proposition.

Today's retarded adolescents are more likely to go to a Naked Gun sequel than a John Waters movie. The laughter level is much higher, and the cartoonishness of the proceedings is part of the point. A Naked Gun film doesn't pretend to be more than a loose assembly of gags and parodies, while John Waters' films aspire fitfully to satire. But satire isn't cool: satire commits you to something uncomfortably like a set of values.

Serial Mom chooses two easy targets, suburbia and the glamorisation of crime. John Waters is too canny to invoke real-life cases (the names Bobbitt and Menendez, as so often, come to mind) which might seem to take American life into domains beyond the reach of satire. If the movie has a point of view, it has to be that the idea of personal responsibility crumbles when people inhabit a world of psycho-babble and gesture politics. Joan Rivers is glimpsed on television interviewing a woman who says of her mass murderer boyfriend, 'I don't judge him,' while Beverly, the heroine of the film, when on trial for her life, is able to discredit the testimony of a witness by exposing her faults as a recycler.

For most actresses, being cast as a crazed killer would be a change of pace, but, despite her wholesome aura, Kathleen Turner has played more than her fair share of monsters - in Body Heat, for instance, The War of the Roses and, above all The Man With Two Brains, where she scaled comic heights beyond anything in the new film. On screen in Serial Mom, though, she has a great inert glow, hair bouncing with malicious purpose as she revenges herself on those who have done her down, face alight with happiness as her fingers punch out the numbers for her next obscene phone call.

John Waters can make some claim to being a cinematic chronicler of his home city, Baltimore, but the portrait of suburbia in Serial Mom turns it into Anytown, USA, a place with no distinguishing characteristics. The heroine makes meatloaf and sings along to Barry Manilow, while her dentist husband shares her love of bird watching, reads Robert Ludlum and has a painting in his office of a huge tooth in the cartoon style of Roy Lichtenstein.

The screenplay juxtaposes images of normality and deviance, but ends up making both seem flat, and oddly interchangeable. One of the few witnesses to the heroine's crimes is a low-life who glanced through a convenient hole in a lavatory stall and saw her lying in wait for her prey with a harpoon. In court, though, he is persuaded to change his testimony by a strange surreptitious exotic glance from the accused, consisting essentially of Kathleen Turner twanging her thighs together under the table, where he alone can see them. Is this polymorphously perverse, or just plain silly?

John Waters doesn't seem to have a lot of affection for his characters, whether respectable or not. The closest he comes to a moment of warmth is a scene where a woman who is shortly to be beaten to death with a leg of lamb puts up her feet to watch Annie on video. Her dog comes in and is encouraged to lick her bare feet. It's almost an Alan Bennett moment, though admittedly an Alan Bennett character would be unlikely to use the phrase 'Get them all wet.'

Perhaps it should be beginning to worry John Waters that the characters he writes who are near his own age are invariably grotesque. In Serial Mom, the heroine's two children are the most sympathetic characters. Presumably he is making a point by having the son, Chip, played by Matthew Lillard, be an addict of horror films without his morals being affected. When Chip's girlfriend sees Beverly on the rampage, she makes the message even more plain, 'It wasn't like the gore movies at all. It was real.'

Beverly's daughter Misty is played by the same Ricki Lake who gave so much pleasure in Hairspray, and perhaps it is here that the decline of John Waters' world is most evident. Lake recently lost eight stone or so and has started presenting her own television chatshow. It turns out that her role model wasn't Divine but Oprah Winfrey all along.

(Photograph omitted)