Food Chain, Royal Court Upstairs, London

The 16-year-old Jamie thinks he's cock of the Islington walk. He has been in a health-warning film about smoking and has signed up to be the brother of the leading character in a forthcoming BBC children's drama. And tonight, he is all set to network like mad at a party for the guy who plays the new black boy in Family Affairs, Channel 5's flagship soap. There's just the little problem of Jamie's behaviour at school, where he is given to smashing other boys' bikes or nicking the underwear from the girls' changing-rooms and scattering it over the playground.

Jamie's parents - Tony, a property-owning cabbie, and his missus - have their work cut out bribing other pupils to remain silent or to take the rap so that the budding superstar is not expelled. Which is how they have come to take Emma, a single mother, and her teenage son, Philip, under their self-interested wing. Never loath to brandish their connections or to kill two birds with one stone, they've invited a local boy who is an award-winning advert director, with a view to pairing him off with Emma and making him reconsider Jamie for a lucrative Oxo-family-like series of ads.

Their world starts to implode, though, when the scheduled guest is replaced by Emma's ex-partner, a rehabilitated drug addict with HIV, and when they get the news that Jamie has been arrested for drug dealing.

Unfolding in real time, Mick Mahoney's highly entertaining new play Food Chain works best when it revels in the boneheaded serials that it satirises. The drama is on less secure ground when it tries to take a morally superior stand. Splendidly played by Paul Ripper, Tony, the ferrety, go-getting cabbie, is a marvellously monstrous creation. He worries so much about status symbols that he can feel deeply threatened just by noticing that he wears his Rolex watch more loosely than a merchant banker in his cab, or go into complete, gabbling denial when Emma turns up in a higher grade of designer shoe than his wife.

There is something almost endearing about his majestic tone-deafness on the PC front ("I drive spastics down to the seaside. I, I recycle!" he remonstrates to the reformed addict) and his crass conviction that everyone is bribable with money and consumer goods ("It's chips and that, so it does everything bar wank you off," he informs a reluctant Philip when presenting him with an unwanted PlayStation 2).

The cast of Anna Mackmin's funny, forceful production in the Theatre Upstairs deliver the quick-fire dialogue with terrific flair. Linda Robson is likeably ditzy as the wife who snorts a line of coke to give herself "a bit of a boost" before setting off to confront the police, and Justin Salinger is suitably contemptuous as the ex-addict who smirks when Tony exposes the shallowness of his culture by not realising that Marlon Brando in On the Waterfront (released in 1954) intoned the line, "I could have been a contender," somewhat earlier than Robert De Niro in Raging Bull.

The snobbishness evident in that last example begins, though, to infect the last stretch of the play. There are clues throughout that Claire Rushbrook's voluptuous Emma is not nearly as hard-up a case as Tony and his wife think. The exploitation may be mutual.

But the final revelation carries the unpleasant suggestion that living on unearned income has become morally preferable to the dirty business of making money, while Jamie's eleventh-hour conversion to honesty feels like a rather tacked-on demonstration that you are what you own up to as well as what you own.

To 12 July (020-7565 5000)