Nick Grosso's sharp-suited lads, knocking back the lagers and whisky chasers in their North London pub, cannot take the Scots as serious paid-up members of the human race, even while admitting (fallaciously, as it happens) that Rod Stewart started out on Clydeside. But the truly serious divide is the Thames, and when they learn that one of their number is to move down south to Streatham they are aghast. Even Stan, the defector, admits that emigration is being forced upon him by his wife, Louise. She really wants to get away, and here's her chance.

Grosso's previous plays, Peaches and Sweetheart, indicated a matchless ear for the revealing concealments of street argot, and here again he gives us the unwittingly comic posturing of council estate twentysomethings, along with those rhythmic deflations that play a crucial role in the conversational ritual. In doing so, he uncovers the strains within a close-bonding male group, fuelled by power struggle and sexual rivalry.

King of the group is Jason Hughes's Tommy - a smoothly assured, mysteriously wealthy character, closer to Louise than the thickish Stan ever suspects. Seething behind his sardonic mask is Joseph Fiennes's Billy, never as close to her as he would like to have been and dripping the poison. Younger than these are Joe and Harry, the first (Jake Wood) always being sent over for the drinks, where girls and calamities spring on him at the bar, while little Harry (Callum Dixon) sits hunched on his chair nursing thoughts of Rod Stewart.

In the opening scene we meet only these four, and there are times when their ceaseless sparring looks likely to become exhausting at any moment. The constant shifting of shoulders under the jackets are the tics of men always readying themselves for their next crisis, the punch-up, the peacock display.

James Macdonald's cast is marvellously convincing in all these details of posture and gesture, and in delivering the patter so weirdly humourless to the speakers.

The first scene of each half is set in the pub, on Rob Howell's remarkable revolve that punctuates the talk by occasionally turning a full circle. The second scenes take us into Stan's flat where Louise (Liza Walker) is forever ironing. Provided you accept the improbable fact of this character choosing to tie herself to Nick Moran's decent but plodding Stan, Walker's spruce performance is rich in nuance, suggesting irresolution and guile in pretty quick succession.

Both these domestic scenes are exercises in seduction, one accepted, the other declined, and the play as a whole portrays a community unlikely to find lasting satisfaction with a mate of the opposite sex, north or south of the river. Or lasting satisfaction in anything longer than a game show on the box or a quick something on the settee.

But Grosso records and shapes the speech habits of this little world into an extraordinarily funny and artistic pattern which can accommodate even the playing of a complete Stewart song, with the revolve spinning round and round like the top of a kitsch musical-box.