FILM / Stripped of the bare necessities: Life, says Adam Mars- Jones, is anything but sweet in Mike Leigh's new film, Naked

Mike Leigh's Naked represents a strong reaction away from the lightness and charm of his last film, Life Is Sweet. It would be hard to imagine a film much sourer than Naked, but sourness is not a fault, merely a characteristic. Hollowness, now, self-indulgence, a sort of gloating emotional ugliness - those are faults.

The film follows the adventures in London of a young man from Manchester called Johnny (David Thewlis), who pays a call on an old girlfriend, Louise (Lesley Sharp), unannounced, and becomes sexually involved with another woman, Sophie (Katrin Cartlidge), who wears mainly torn fishnet, temporarily resident at the same address. Johnny chooses to spend the night on the streets after poisoning any welcome he might have had at his old flame's place of residence. He came south in a car, but no reference is made to that from the moment he parks it. He could go somewhere else, he could sleep in it, if need be in the morning he could sell it, but no. The car has not been invited to take part in the improvisation sessions of the Leigh method, and for cinematic purposes has ceased to exist.

It's a new departure for a Mike Leigh film to be so dominated by a single character, and Johnny's worldview goes pretty much uncontested. It helps that he's the only one who has a worldview, with the possible exception of a night-watchman implausibly attuned to Johnny's preoccupations, except for not being particularly clever or funny. Johnny's worldview is sardonic, virtually nihilistic and highly artificial. No matter to whom he's talking, and whether he's exhausted or indeed injured, he produces downbeat wisecracks in a steady flow. In the short term these are amusing, in the long run merely irritating, and though irritation has always been a permissible reaction to Leigh's films - so often his characters exist on the edge of caricature - never before has it been compulsory.

Another novelty in Naked is the amount of sex, virtually all of it amounting to genital expression of men's hatred. Besides Johnny there is Jeremy (Greg Cruttwell), a sadistic yuppy. Anyone who remembers the yuppy characters in High Hopes, who had a class-bound way of doing everything, even going upstairs, may be prepared for Jeremy, but anyone else is likely to be mystified. What's the point of a three-month rehearsal period when you can just go along to Oxford Street and have a T-shirt printed with the words 'SADISTIC YUPPY' while you wait?

Jeremy's character is no more rounded than that. He goes to the gym, he drinks champagne, he has a car phone. But the details that aren't stereotypical are nonsensical: he drives an A-reg car and he leaves pounds 380 in cash as humiliating compensation after brutalising Sophie.

Both Jeremy and Johnny are vile to women, but where Jeremy's cruelty is a pure expression of privilege, we are encouraged to think that Johnny's cruelty is a cry of pain. If you believe that, you'll believe anything. Either that or Leigh is saying with equally crude manipulativeness, that's how men are. Naked certainly doesn't show women the way they are, unless women are inert masochists who may or may not even notice they've been raped. A character whose fakeness almost eclipses Jeremy's is Sandra (Claire Skinner), the nurse who owns the flat where Louise lives (and Sophie crashes), and returns from holiday in Zimbabwe to find her home in turmoil. Sandra is given a foolish costume (bush hat, shorts, socks and sandals), a silly posh girly voice, choppy hand gestures, a habit of not finishing her sentences and an implausibly dated vocabulary ('I don't need all of this palaver', 'it's the tin lid'). The only remotely subtle bit of characterisation on offer is the presence in the bathroom of an NHS Property towel.

Naked, with its London locations and its emphasis on social casualties, on the walking wounded of the inner city, would seem at first sight to belong to a particular British tradition of downbeat realism. But when at a late stage of the film Sophie, the mumbling Goth, mentions that she once had a lover in Paris who was a philosopher, or when an ageing prostitute turns out to have a tiny library that includes both Emma and The Godfather, we know that realism isn't in it. Viewers of Naked are in fact being offered a highly specific set of distortions. The most noticeable consequence is that anyone with a career or even a job is regarded as inauthentic by definition.

This tendency is not altogether new: fans of Life Is Sweet may remember that the sister who was a plumber was treated with respect, while the entrepreneur played by Timothy Spall was a complete grotesque. To be disaffected, to be a misfit, on the other hand, is in Naked to be existentially real.

If this is part of Leigh's ideology, then it is a hypocritical one, since he is himself a successful small businessman. But there may be a more eccentric explanation. Time to take a deep breath. This review is about to enter, on tiptoe, two areas of near-taboo in criticism of Mike Leigh - his method of structured improvisation, and his class consciousness - and to try and find a link between them.

Anyone involved in a Leigh film offers the rigour of his working methods as a sort of guarantee of the truthfulness of the end product, while at the same time it is illegitimate for a critic to pronounce on the method as opposed to its results. But when what appears on screen is not just untruthful but crashingly untruthful, it's impossible not to speculate.

When Greg Cruttwell is on screen he seems to be approaching every action with reference to his character's status: how does a sadistic yuppy enter a room? (With a cruel smile.) How does a sadistic yuppy go to sleep? (With an empty bottle of champagne.)

Claire Skinner is similarly determined, hellbent on producing a performance that will say patronising nurse, like a stick of rock, wherever it is sliced.

Conversely, dispossession for the character translates into freedom for the actor. Johnny is far from his home, he doesn't have a job, a history or any context of relationships, and so David Thewlis can go to town with him.

Language only betrays the status- bound characters Jeremy and Sandra, but Johnny's use of language is his essence, and Sophie has only a little less freedom to invent herself.

The film that results from the collision of these incompatible acting exercises is, among other things, much too long. It could lose 20 minutes and still not seem short. The actresses playing Louise and Sophie make the most impression; they achieved the grinding familiarity of people you don't like but are going to have to deal with somehow, as if you'd married into a family and found yourself saddled with them as in-laws.

From Johnny, though, for all the perverse love that actor and director have lavished on him, it is easy to get the emotional equivalent of a quickie divorce.

(Photograph omitted)