Ayckbourn proves that two into one does go

House and Garden | National Theatre, London

Talk about a takeover at the National. It is some time since Alan Ayckbourn has had an original work mounted at this address, but his return now is not so much a visit as a full-scale occupation. For the next few weeks, House and Garden, his ingenious comic double act of dramas, will be monopolising not just the Olivier and the Lyttelton stages (leaving the smallest auditorium to that young unknown, Arthur Miller), but also annexing the large Lyttelton foyer for the spoof summer fete that ends the afternoon-and-evening marathon. This is the quest for Lebensraum with a vengeance. If I were Trevor Nunn, I would be doublelocking my office.

Talk about a takeover at the National. It is some time since Alan Ayckbourn has had an original work mounted at this address, but his return now is not so much a visit as a full-scale occupation. For the next few weeks, House and Garden, his ingenious comic double act of dramas, will be monopolising not just the Olivier and the Lyttelton stages (leaving the smallest auditorium to that young unknown, Arthur Miller), but also annexing the large Lyttelton foyer for the spoof summer fete that ends the afternoon-and-evening marathon. This is the quest for Lebensraum with a vengeance. If I were Trevor Nunn, I would be doublelocking my office.

In Noises Off (soon to be revived at the National), Michael Frayn famously revolves the action so that you are alternately privy to the onstage and the backstage antics of a frightful rep farce. House and Garden plays a witty variation on this conceit that every exit in life is an entrance somewhere else. Here, Ayckbourn has the same set of actors racing between two separate but interlocking dramas that cover simultaneous events and are also, by a devilish twist, performed simultaneously in two different theatres and before two distinct audiences.

This diptych was unveiled last summer in Ayckbourn's Scarborough home base, where the dash from one auditorium to another is a relatively easy sprint. There is, however, an added piquancy in the author's expertly drilled and semi-recast production for the National because the greater distance between the theatres creates a logistical backstage nightmare of colour-coded staircases, frazzled stage managers and breathless, colliding thesps. It can't be long, though, before someone writes a farce about just such a perilous behind-the-scenes predicament.

Reflecting on the overall wizardry of the event is quite a bit more fun, I feel bound to say, than the experience of watching the plays consecutively. They are set in the sitting room and the stately grounds of Teddy Platt, an adulterous country grandee (played by an excellently hapless David Haig) who is being sounded out by a visiting old schoolfriend and political fixer (the wonderfully cold-blooded and lizard-like Malcolm Sinclair) about standing as the local MP. Teddy's political prospects are not exactly enhanced, however, by the fact that his offended wife (starchy Jane Asher) is now refusing to acknowledge his existence, or that, out in the garden, his mistress (hilariously crazed Sian Thomas) is undergoing her own marital breakdown from Michael Silberry's culpably innocent morris-dancing buff, Giles. To put the tin chapeau on it, there is the terminally disruptive arrival of an unstable, glamorously sexy French film star (Zabou Breitman) who winds up opening a good deal more than the downpour-bedevilled fete.

Playing in front of two audiences at once must feel like a form of bigamy or adultery, but House and Garden doesn't make enough of the way the two-timing of the characters is mirrored in the form. Despite the publicity, neither is really free-standing. Indeed, Garden is so much the weaker piece that you feel as though you are attending a piano recital where the instrumentalist has elected to play only the left hand of the music. Given that they have to adjust their timing to the differing levels of audience appreciation, this inferiority must be a further headache for the performers.

In both plays, though, there are indubitably entertaining patches and familiar Ayckbourn preoccupations as three marriages founder through the blithe male insensitivity of good as well as bad characters. You don't need to be the fortune-teller at the climactic fete to predict that the National have a nice, safe middlebrow summer hit on their hands.