Catch, Royal Court Theatre, London<img src="http://www.independent.co.uk/template/ver/gfx/threestar.gif"></img >

Big Sister is watching you

The Government has yet to convince a reticent public to commit the finest details of their identity to a piece of plastic and a national database. After watching Catch, a nightmarish vision of life under the beady eye of Big Brother, it's not difficult to see why.

Catch rounds off the Royal Court's 50th anniversary year by repeating an artistic experiment from the theatre's history. In 1971, seven young male playwrights, including Howard Brenton, David Hare and Stephen Poliakoff, collaborated on a play, Lay By. Thirty-five years later, the Royal Court's artistic director, Ian Rickson, has gathered a group of five female playwrights - April de Angelis, Stella Feehily (O Go My Man), Tanika Gupta (Sugar Mummies), Chloë Moss and Laura Wade (Breathing Corpses) - for a similar collaborative effort.

Their play is a reflection on identity, not just as the latest burning political issue, prefixing the words theft, card or database, but as a deeper malaise at the root of modern society. We live in a culture of alienation where people are divided into urban tribes - hoodies, posh bitches, druggies, or, as the hijab-wearing teenage character says, "fellow Ninjas" - or by alphabetical market research classifications.

Claire is an "identities re-actualiser" and the head of Chrysalis Identity Solutions, a shady company that offers support to those in need of a change in identity, whether to obtain a better mortgage or to regain a lost sense of self. "It's never about 'who you are' - but 'who you appear to be'," she tells one client.

We are, apparently, "like dripping taps" with our personal information. Having compiled a 50-page dossier on a person - their address, their shopping habits, favourite foods, preferred brands, medical history - Claire offers advice on how they can upgrade, for example, from a "category E-F" to "super classification C"; it can be as simple as moving from a council to a rented property and stopping the weekly shop at Iceland. But Claire's obsession spills over into all areas of her life: boyfriends are categorised before the dinner date has even begun ("I knew you and I weren't the right types for each other... you're a B2"), CCTV cameras are her friend and comfort, and she has, to put it mildly, some identity issues of her own. Tanya Moodie is majestically creepy as Claire, mouthing platitudes and jargon as she spins her mysterious web around her precious clients.

Her office lies at one end of a desolate underpass, the hangout of a group of feral young chavs and hoodies. They might be stereotypes with their box-fresh trainers, hoop earrings, street talk and violent addiction to happy slapping but they are no less terrifying for that. Farzana Dua Elahe and Niamh Webb are lively as young girls whose position in society is pre-determined. Growing up "with the furniture of surveillance" their life and behaviour only has meaning if it has been recorded. Polly Teale's direction is pacy and merciless. A traverse set evokes the detritus-strewn subway, allowing for a dynamic flow of scenes punctuated only by the harsh flickering of overhead fluorescent strip lights.

That five playwrights have had a hand in Catch is evident, but the different voices enhance the social tapestry of the script. More problematic is the fact that the interwoven strands are forced to come together in an accelerated and melodramatic way, rendering the second half much less gripping than the first. Betraying its workshop origins it's a little schematic and heavy-handed in places, although Kathryn Drysdale as Maya, Claire's work-experience candidate and the voice of reason, deals admirably and sweetly with some didactic lines. It's still a powerfully unsettling portrait of 21st-century urban life and an impressive showcase of all five playwrights' ear for dialogue, vernacular and, in some welcome places, comedy.

To 22 December (020-7565 5000)