THEATRE / Benny and the jesters: Paul Taylor on Dead Funny at the Hampstead Theatre

Terry Johnson is noted for contriving dramatic encounters between unlikely luminaries: Marilyn Monroe and Einstein in Insignificance (1982) and Freud and Salvador Dali in Hysteria, his recent, highly amusing intellectual farce. A different sort of coincidence involving celebrities provides the springboard for his new play, Dead Funny, which takes off from the fact that Benny Hill and Frankie Howerd died within a few days of each other in the spring of 1992.

The play takes an uproarious look at the impact of this double blow on the Dead Comics Society, a group of devoted suburban comedy buffs (the sort who put up plaques to Hattie Jacques and can do the Morecambe & Wise 'Boom, ooh, ya-ta-ta-ta' sketch word perfect). Ending in the 'memorial do' for the late Benny that turns into both an unscheduled coming-out party and a slapstick scrimmage, Dead Funny demonstrates that, though the English pride themselves on a sense of humour, what they mean by that term is often the sort of thing you'd need a very active sense of humour to survive.

Johnson brings this out by presenting us with a strikingly dysfunctional marriage. Forty-one and going mad for want of a baby, Ellie (Zoe Wanamaker) has to cope with a husband, Richard (David Haig), gynaecologist and proud chairman of the Comics Society, who for the last 18 months has decided he doesn't want to be touched. You see what she's got (and hasn't got) on her plate in an early scene when a sex therapy session of 'sensate focusing' with her naked and very reluctant spouse is interrupted by a gay neighbour (Niall Buggy), hot with the news ('There's no easy way to say this') of Benny's demise. Not even a lovers' guide video ('Foreplay's a moveable feast,' we hear one flat-vowelled, irksomely sharing voice confide) can get him back in the mood now. He's too busy on the phone breaking the tragic tidings to other members.

The irony of this marital situation is that it's turned Ellie - regularly patronised for having no sense of humour because she refuses to partake in the 'joy of simple laughter' - into a scathing comedienne. Her withering put-downs and provocatively sick retorts, which are fired off with blistering power by Wanamaker, offend the others in principle as well as in content. 'When you have become a mother, Ellie, you will realise that some things just aren't funny,' says a pursed, sanctimonious Lisa (brilliantly played by Beatie Edney) whose on-the-side sexual favours have been the cause of Richard's 'celibacy'. You realise that, for people like Lisa, rehearsing old sketches and routines is the substitute for wit and humour, not their expression. This reviewer was reminded of the Monty Python-bores he suffered at school - the more comprehensive the recall of the material the more monumentally humourless the person by and large.

It would be misleading to suggest that Dead Funny is a companion piece to Trevor Griffiths' Comedians, doing for the response to comedy what that play does for its communication. Johnson's piece doesn't work in such a systematic way. None the less, there's a wealth of suggested truth about this topic in, say, Richard's only happy memory of his father: doing a Max Miller impression every Boxing Day. The fact that the spirit of that routine didn't spill over into the rest of life (but was just a respite from it) is the bleak joke about avid comedy-consumption that the play illustrates in high-spirited ways. It's ironic, too, that Richard can see no similarity here with his own case.

There are some deliriously funny routines, such as the one where an unwitting husband (Danny Webb) arrives at the final party impersonating Benny Hill's Mr Chow Mein character, whose Chinese accent converts every innocent remark to filth. Given that his wife has just been rogered by Richard in that very room, comments like 'he slip in his cock' ('he sleeps in his cot') have a far from calming effect. Johnson directs a crack cast in a splendid production that threatens to veer into sentimentality in the final moments, while deftly avoiding it. It may sound like some naff comedy thriller starring Donald Sinden, but Dead Funny is in fact a spot-on self-description.

Hampstead Theatre, London NW3 (071-722 9301)