The Independent Collector: John Windsor's Guide to collecting contempora ry art: Hannah Starkey

A MOTH that landed on a navvy's jumper ended up as the centrepiece of Hannah Starkey's best-known photograph. Most great photographers have their signature works - Cartier-Bresson's photograph of a boy proudly carrying home two bottles of wine, for example, or Man Ray's nude, Kiki, with cello sound-holes superimposed on her back.

At 27, Starkey has most of her career ahead of her, but her photograph with the moth - a massive 4ft by 5ft colour print - has already been singled out by critics as the most representative of her work. Charles Saatchi has bought one.

Starkey, whose solo show is at Maureen Paley's Interim Art Gallery, had sought a moth or butterfly for a month. She did not know how to go about trapping one, and balked at paying the Natural History Museum pounds 100 to hire a dead one. Then, on the day of the shoot, she spotted a moth clinging to the jumper of a man digging a trench in the road in Hampstead, and nabbed it. Her Surreal intrusion, she reports, did not perturb him a bit.

Moths and butterflies, she felt, as well as being enchanting signifiers of transience, engage the attention when we are killing time in a cafe, or sitting in a bus or tube train, absorbed in the sheer banality of existence.

Her photographs bring banality to life. In what may seem to be a void of urban alienation, a lot goes on. The senses sharpen. People begin to observe other people. Every detail of their looks and behaviour becomes magnified. A sort of silent communication takes place.

In this scene, models were photographed in the Formica-clad banality of a London Bridge cafe, one woman toys vacantly with the moth while another looks on, transfixed. Their eyes do not meet directly, but in the mirror's half-real reflection they acknowledge each other.

Starkey intended her series of photographs simply to illustrate how women observe each other. But their urban environment proved to be an unexpectedly powerful element. Their soft, rounded forms are shown enclosed within the harsh geometry of man-made architecture, with its unrelenting right angles, semi-circles and hard, shiny surfaces.

Trapped in such claustrophobic spaces, observer and observed silently exchange their opinions of one another - and their petty resentments. Tension rises. In another photograph, a mother and daughter returning on the tube from a shopping trip sit together without speaking. Either the mother will break the tension by making a flippant remark, muses Starkey, or there will be an explosion of recrimination that has been building up all day. On the top deck of a bus, one woman eyes another eating an odorous McDonald's take-away meal in a seat in front of her. The resentment is almost tangible. The snacker is slightly hunched, as if expecting a blow from behind. As for that moth: what on earth is that woman doing with it? Why can't she leave it alone?

Starkey's works are untitled, which means that it is up to the viewer to interpret what is going on. Different people may come up with different conclusions, but she does not mind that. Her photograph of an old woman sitting in front of a bedroom mirror is quite a puzzle. It turns out that it is the woman's guest bedroom, not her own. I will not give away the clues.

Her models are out-of-work actresses who answered her advertisements in The Stage. The actress in the moth photograph is wearing curlers. She intended to take them out just before the shoot, as professional models do. Starkey told her to keep them in.

Starkey graduated from the RCA last year. Her 4ft by 5ft prints, in editions of five, sell for pounds 2,500, her 16in by 20in prints, in editions of 15, pounds 600. Besides Saatchi, the V&A and the Tate Gallery have bought her work. What happened to the moth? After the shoot, she released it in the street.

Hannah Starkey: Maureen Paley Interim Art, 21 Beck Road, London E8, until 28 November (0171-254 9607). The New Neorotic Realism, Saatchi Gallery, 98a Boundary Road, London NW8, 14 January to 28 March 1999 (0171 328 8299)