THEATRE / Just the right treatment from Crimp at the Court: The Treatment - Royal Court; A Love Song for Ulster - Tricycle; For Services Rendered - Old Vic; A Jovial Crew - The Pit

TWO FILM producers in New York buy up the life story of Anne, a girl who has run away from her husband because he tied her up and put sticky tape across her mouth. The producers like the detail about the sticky tape. It's silver, so on film it will catch the light. They pull in a writer who has a voyeuristic twist to add and a famous actor who requires a producer credit and complete control. In no time Anne's story is out of her hands. Even the secretary points at her saying, 'this is not my idea of Anne'.

The Treatment, the new play by Martin Crimp, gets just the right treatment itself from Lindsay Posner's polished, acidic cast. When the secretary (Geraldine Somerville) reads out the whole script report in front of the writer - a bold and skilful scene - the producers (Sheila Gish and Larry Pine) react to each twist with a sly tilt of the head or a narrowed eye. The suspense is perfect. The secretary finishes the report and there's a pause, before the laid-back Pine gives his approving verdict: 'It's a mindfuck, Clifford.'

This sushi-bar world of 'facilitators', the sort who would rather read a menu than a play, is laid bare in an idiom as luminous as the neon lights on stage. Crimp sculpts apparently shapeless speech - overlapping lines, simultaneous conversations, stacked thoughts, delayed replies, hesitations, interruptions and repetitions - into something telling. He is wonderfully attentive to the status details these mannerisms reveal. Half the fun lies in what he leaves out: a tradition of rhythmical ellipsis that stretches back from Pinter to Coward. Twenty minutes into The Treatment, the thought that kept surfacing was simply: can this last?

It doesn't quite. The grip slackens, and a couple of scenes wobble badly. But there are great moments on the way: the script conference, the seduction, and, surreally, the lift the blind cab driver (a lovely cameo from Marcus Heath) gives the blind writer ('Let's try taking a right here').

Anne has to decide which is worse, her husband's sticky tape or the less visible gagging she receives from the film industry. The bitterness of the moral is nothing to the flair with which it is delivered. Crimp tends to work as a miniaturist, but in The Treatment he scotches those 'promising' quotes that hung around his name in the Eighties, and gives us a wickedly funny main-house play.

A Love Song for Ulster is a bold trilogy by Bill Morrison. It follows a family from the partition of Ireland in 1921 to the present day, and turns in on itself again and again. By the final play - The Daughter - a young woman is pregnant by her cousin, though his father shot her uncle, and her brother shot his father. But Morrison's ambitions go beyond a mere six-hour saga spanning 70 years. He is after symbolic status.

The British officer naturally stands for the British army and the fight for control over the house stands for the wider conflict. In the first play, The Marriage, we see Victor, a Protestant, raping his Catholic sister-in-law on the kitchen table, literally over the dead body of his brother. The violence is disturbing, but so is the clunkiness of the image.

The cast is strong enough to fill in the outlines. As Victor, John Keegan journeys from a young political bigot to an old religious one poring over the Bible. His refusal to give away an inch of land, let alone cook his own supper, forms one of the best scenes in the trilogy. The hope is that by following individual stories we will find wider insights. Here we kick off with generalities. There was more to be learnt about Ulster from Rian Malan's article in this month's Esquire.

Somerset Maugham's For Services Rendered, which transfers from the Salisbury Playhouse to the Old Vic, finds improbable new relevance in the recession. The injustice meted out to war veterans fades next to the problem of the local garage business going bust. Still, pity the actor today who makes an entrance in a straight play wearing blazer and plimsolls and waving a tennis racket. It's hard to reach out beyond the stereotype.

As the mother with the terminal illness Sylvia Syms anchors the play with understated depths, and Terry Taplin, as the older man making a damn fool of himself over a young girl, clenches and unclenches his fist and we're in the palm of his hand. The rest of Deborah Paige's production lacks the detailed ensemble work required to bring a period piece like this back to life. It was there at the National in 1979, but not here.

Max Stafford-Clark's revival of Richard Brome's A Jovial Crew, recommended by Irving Wardle when it opened in Stratford last year, reaches London. This masterly production about the beggar's life is a real find: balancing the clamour of good company and the mystery of the road with the realities of homelessness and home comforts. From fastidiously flicking through his master's accounts to flamboyant dissembling on the open road, Ron Cook's steward turned beggar deserves all the loose change you have.

'The Treatment', Royal Court (071-730 1745). 'A Love Song for Ulster', Tricycle (071-328 1000). 'For Services Rendered', Old Vic (071-928 7616). 'A Jovial Crew', The Pit (071-638 8891).

Irving Wardle returns next week.