Jake and Dinos and all their little friends

'A scatological aesthetic for the

tired of seeing' - or just mindless

obscenity? Peter Popham meets

two artists who 'make Damien

Hirst look like the Angel Gabriel'

"D'you watch Neighbours?" Jake Chapman asks me. He grasps the child-sized mannequin by its horns and wheels it round for my inspection. "Look: Annalise!" And it's then I notice that the plastic things sprouting from the child's temples are not horns but erect penises.

Jake and Dinos Chapman are setting up their new exhibition at the ICA in the Mall. It is the biggest and most high-profile show they have yet tackled. Everything in it, including "Annalise", is completely new. It has taken them five months to complete the 15 pieces.

Downstairs, a large room has been carpeted in plastic grass. This will be the introduction to "Chapmanworld", as the show is called, a playground for the sort of figures that have brought the Chapmans to the public's attention over the past year or so: the child mannequins with the honeyed skin, shining hair, and large, watchful eyes of department-store dummies, who just happen to be joined at the waist - or joined at the face, with a vagina at the join - or endowed not with a cute little nose but with an erect penis instead, and with an anus in place of a mouth.

In two further rooms upstairs, the brothers are hard at work. Like the Disneyworld of which it is a distant, macabre parody, "Chapmanworld" is designed as a work of theatre, with its own particular jolts and frissons. Already the components of the tableau are beginning to come together here. On the trunk and branches of a miniature tree, sprouting with green leaves, a gaggle of small child-mannequins disport themselves. There is nothing wrong with them except (as Dinos points out) that the small child with the Afro wig has a small cut on his knee. "Presentiments of things to come, perhaps," he says with a sinister smile.

They are all naked, and they have no genitals. Nothing odd here: when was the last time you saw a shop-window mannequin with fully formed genitals? "It's really quite nice that our work has achieved the position whereby we can show a series of mannequins without any genitalia," says Jake. "It seems relatively mild in opposition to the more pathologically obvious stuff - yet it seems to me more pathological that they have no genitals."

There is a persistent sound of dripping in this room. Coming round the tree, we see in the next room blood-like stuff dripping into a bucket, the drips amplified through loudspeakers. But it's only when we step into the room that we see the crowning horror of "Chapmanworld".

A beautiful silver-fibreglass figure of a man is suspended upside-down from the ceiling. Here and there raw red wounds have been opened in the silver skin, and the "blood" is pouring out of them. The man is modelled on a photograph from the last days of Imperial China of a prisoner dying the "death of a thousand cuts". (The photograph is reproduced in a book by George Bataille, The Tears of Eros.) From the bucket, the "blood" is pumped back up to the ceiling to resume its journey through the figure's body.

Jake and Dinos Chapman have found fame using the same means employed by almost every successful artist since Francis Bacon: shock effect. Shock is much the most important weapon in the modern artist's armoury, the one thing that, like technical virtuosity a century ago, can guarantee attention. But shock tactics can backfire, too.

This is what has happened with the brothers Chapman. Writers in two Sunday papers have called them "fascist" (apparently in the sense of "very unpleasant"), a third remarked that "these boys make Damien Hirst look like the Angel Gabriel". Various other journalists have reeled away from encounters with them, complaining about rudeness, puerility, refusals to answer questions and being dumped on from a great height by mounds of pseudo- post- deconstructionist gibberish.

It's true that the Chapmans are stingy and sometimes plain misleading with information about themselves. They appear to have been raised in Cheltenham; both did first degrees at art colleges (Dinos at Ravensbourne and Jake at North London Poly), then came together at the Royal College of Art in 1988, where they both got MAs. They began exhibiting singly in 1992, and together the following year, with a work, The Disasters of War, which was a version of Goya's gruesome series of etchings of that title in the form of painstakingly carved plastic soldiers. They live and work in London's East End. The rest is silence. "People always ask about our parents, our backgrounds," says Jake, "but we're wary of the biography being the redemptive angle for the work - the idea that, if you get nothing from the work, you go back to the oedipal relations with the parent, and so on."

They are both rather tall and, nearing the end of this epic project, stubbly and tired-looking. The main peculiarity about them is that Dinos, though four years older at 34, looks and behaves like the younger; Jake, with his sinister good looks and determined chin, does all the fancy talking. Dinos, dozy-looking in granny glasses, keeps his mouth shut, occasionally opening it long enough to put his foot in it (as when he told the Observer that visitors to galleries should be means-tested to keep out the stupid).

Talking of shock effect, I mention that another journalist quoted them as saying that their goal was to stop the "chattering classes" chattering. "I'd like to make their chattering become something more physiological, something more like laughing - a hernia here or there would be quite good," Jake responds. "Most attacks we get are for being gratuitous or, as other people have said, crassly sensationalist. We've always seen the crassly sensational as being a really interesting area!"

So is that what they are aiming for?

"I think we're aiming to produce works of art that neutralise themselves in a way," Jake goes on. "It would be similar to, say, a Beckett text which makes utterances yet no sense. That's what we're trying to do: waste space and time."

The Chapmans have caused not merely shock but deep offence because their work compulsively mixes up images of childish innocence and adult sexuality, pitiable images of deformity with scatological sexual gags straight off the wall of the public lavatory. But what gives their work a sinister and ungraspable power is that the execution of all these horribly disparate elements is uniformly slick and industrial. As Jake puts it: "We get mannequins and chop them up and rearrange their positions and so on ... The thing with all our work is the degree to which you have to manufacture something until it actually looks manufactured, so you've effaced every trace of spontaneous decision-making. Aesthetically tangible marks have to be lost."

Dinos: "... which entails more work than actually leaving marks."

The intensely artisanal process of making their work, therefore, is necessary to remove all trace of its artisanal origins. Two-Faced Cunt, Siamese Fuck-Face and all the other delightfully named brethren are thus linked visibly with the world of the shop-window commodity: that world of perfection, vacuity, cliche and endless repetition in which the Chapmans romp and play. The mannequins which are the Chapmans's raw material are "easy on the eye" the way Burt Bacharach is "easy on the ear". Their achievement is, while keeping rigidly within the grammar of the mannequin, to make them impossible to look at. They are not ugly or obscene in any normal meaning of those words; it's just impossible for the eye to rest on them without immediate distress.

Why should this be of interest? Why should anyone beyond the bounds of the ICA's mailing list be interested in having such stuff inflicted on them? By using mannequins in this way, the Chapmans are shoving in our faces the fact that we are buried up to our necks in the world of manufactured commodities, so that our eyes like our other senses and appetites are completely jaded and saturated with industrialised cliches. This saturation is far greater now than it ever was in the past, to the point that it is almost impossible for us to see things freshly: everything our eyes alight on we have already seen a million times before. Redeeming our corrupted eyes is part of what the Chapmans are attempting: to create, as they put it, "a scatological aesthetic for the tired of seeing".

Perhaps shock is the only way of doing this. I think the peculiar strength of the Chapmans' work - reflected in the virulence of the criticism they have received - is that even more (and far more articulately) than Damien Hirst, they are rediscovering visceral, theatrical possibilities of art that have been in abeyance for years.

Conceptual art - Andre's bricks, Whiteread's house, Christo's wrapped Reichstag - is relentlessly cerebral. The Chapmans are cerebral, too, and like all avowedly modern artists, they are in the business of subverting established taste. But you have to go back to the Surrealists to find artists so bent on kicking the viewer in the eye, shaking him by the shoulders, making him see anew. And willing to devote such resources of puerile humour, bad taste and out-and-out laddish rudeness to getting results.

! ICA, SW1 (0171 930 3647), to 14 July.