Art - Michaela Gall is impressed by Sam Taylor-Wood's vast mural for Selfridges

Giant billboard art - the kind that covers an entire building - is something that you'd normally associate with megalomaniac portraits, from which the likes of Chairman Mao or Fidel Castro might glare down. In the capitalist west, we have to make do with advertisements for Gap on an altogether less ambitious scale to provide some kind of street art - until now, that is. Selfridges has commissioned the Turner Prize finalist Sam Taylor-Wood to wrap its entire Oxford Street store in a vast artwork while renovations are carried out on the building underneath. The artist told me that the only stipulation in an otherwise open brief was that there should be no explicit nudity - something that, as visitors to the Tate Modern will know, features fairly regularly in her work.

Taylor-Wood has created what appears to be one ingeniously long photograph running around three sides of the building (making it 900-feet long), but which is, in fact, three panoramic shots taken with a revolving camera and spliced together. The camera takes five seconds to complete each 360-degree revolution, hence the work's title: XV seconds.

The artist sees the work as "a contemporary version of the Elgin marble frieze from the Parthenon, peopled with modern-day 'gods' to adorn a temple of shopping". Taylor-Wood approached her "gods" in the form of a letter asking them to take part in the shoot, and most were delighted to oblige (except for Michael Gambon, who never showed up). Centre stage in the frieze sits a 40-feet high Elton John crouched bullishly over the main doors of the great emporium, looking less like the god of shopping than the newspaper baron from a painting by Ingres (Manet referred to Ingres's sitter as "the Buddha of the bourgeoisie"). Around him, assorted dancers, actors, models and a chef stand or lounge in a series of louche tableaux adopting poses struck by some of art's famous figures. Here is the naked back of Ingres's voluptuous bather; there a couple of girls grapple in a scene from a Roman painting; while the actor Ray Winstone puts a finger to his head in a gesture reminiscent of Robert de Niro in Taxi Driver.

But there is a disconcerting lack of interaction between most of the participants; even the couple whose fingers touch in a hommage to the Sistine Chapel appear to be making an arbitrary connection. This "dysfunctional narrative" is something of a hallmark of Taylor-Wood's work. The feeling of unreality, that we're not quite seeing the whole picture, is emphasised by the subtle distortions that permeate the piece: characters appear more than once, others are slightly elongated (Richard E Grant's head goes right out of frame). The apparent candour of the photographic surface is, in fact, gently subversive. There's a weird feeling, too, that these characters are standing on the outside, not just of Selfridges but of the room at Peacock House, in Holland Park, where they were photographed. The room, lined in gorgeous turquoise tiles, becomes one linear strip, creating a 2D effect that makes everyone look like they're standing on a shelf, and simultaneously removes a sense of real space.

So does it lure in the shoppers? When I joined the hundreds in Oxford Street on a stormy May afternoon, the giant hoarding was attracting some attention, and the enormous central figure of Elton seemed to be the hook that drew people in. Taylor-Wood wanted people to feel curious, "so they would walk round the whole of the building to have a look". To this end, she made both corners of the frieze arresting: a figure with his arms out as if he's being crucified has the effect of pinning you and him to one corner, while the opposite end has actor Adrian Dunbar pulling model Alex Wek reluctantly around the bend - or is it the other way round?

The sheer scale of the piece is a technical feat; it is the lar-gest photograph ever made, so large that an aircraft hangar had to be commandeered to hang up the test sheets. The only disappointment is that a better resolution wasn't possible. The finished work is made just like the giant advertisements, but it lacks the bright colours and contrasts of high-quality reproduction. Still, this is an enlightened idea, and it could be the way to transform all those building-sites wrapped in flapping tarpaulin of which our cities seem so fond.

This article first appeared in the 05 June 2000 issue of the New Statesman, Driving back to happiness