In February, after a session on his osteopath's couch in Scarborough to treat routine wear caused by almost 50 years of writing and directing in theatre, Alan Ayckbourn tried to get up and couldn't. This sounds like a very Ayckbournian comic scene - the physiotherapy session that leaves you worse than you went in - but, in fact, a potential tragedy was developing: the playwright was suffering a stroke.
As he explains: "An hour before, I'd jumped out of a BMW convertible, a perfectly healthy man. But I left on a stretcher." Having avoided a single admission to hospital during his 67 years, he was now beginning an eight-week stretch: longer than any of the many rehearsal periods filling his diary at the Stephen Joseph Theatre he runs in Scarborough. The stroke progressed throughout his first hours in hospital, claiming his left side from foot to face.
Was he frightened? "Very. During that first night. There was one poor nurse I think I almost reduced to tears. I was holding her hand and saying, 'I can't be here. There are all these things I have to do.' And she said, 'Well, you won't be able to.'"
After a summer of recuperation, Ayckbourn, on a sofa at his Scarborough townhouse with a view of sun-glittered sea, is recognisable as the friendly, energetic presence of interviews before his illness, although his enthusiastic, actorly voice occasionally snags, like a tape played on dodgy sprockets in his long-ago days as a studio-manager for BBC radio. The only other sign of the recent crisis is a left leg that doesn't immediately kick in when standing up.
However, the part of his brain that provides the comic observation seems completely intact. Hospital anecdotes flow. Early in his stay, two medical students arrived to take a blood sample. Ayckbourn warned them that he was prone to fainting - he had once halted Anthony Hopkins' King Lear at the National by passing out in the stalls during the blinding of Gloucester - but they proceeded anyway. The next thing he knew, the room was full of doctors and trolleys and electrodes were being placed on his chest.
On another occasion, a sudden leak in an air bed intended to prevent pressure sores led to the writer being "raised into the air on a hoist, hanging above the bed for hours like a giant baby about to be dropped by a stork".
Many stricken dramatists would immediately have turned this grim experience into a script - Dennis Potter got single plays and a six-part television series from his hospitalisation with psoriasis - but with Ayckbourn the connection between experience and creativity has always been more complicated.
Unless you happen to be a wife or son of Alan Ayckbourn, it is impossible to know how autobiographical his plays are. To an outsider, they seem to have been drawn from a sort of social war reporting - the entanglements of marriage and friendship in The Norman Conquests, or a near-suicidal woman in Just Between Ourselves - or train-set playing with the possibilities of the stage: a single cast performing two interlocking plays in adjoining theatres in House and Garden.
So does he expect to write a hospital or medical comedy? "I might do. I think writing a play about a man who has a stroke isn't really me. But I think I might use some of the experiences." For example, he suffered a relatively common side-effect of strokes: a confusion between the words "yes" and "no". In hospital, the patient would believe that he had cheerfully agreed to an offered cup of tea and then be dismayed when the trolley was, with apparent cruelty, wheeled past. When a reversal of word-circuits was diagnosed, he was referred to a speech therapist: "She sat on the side of the bed and said, 'Are you aware you're doing this?' I said, 'No.' After which we looked at each other and she said, 'I don't think there's much point in this conversation.'"
Amused by the dialogue possibilities, Ayckbourn is contemplating a play called The Man Who Couldn't Say No. But the question of whether the writer will dramatise his illness is complicated by the fact that the play he finished before his collapse bizarrely anticipated his condition.
If I Were You, Ayckbourn's 70th play, which he finished in January, is a sort of sex-swap comedy, in which macho husband Mal and pliable wife Jill wake up to find that they have swapped personalities during the night: though outwardly unchanged, each now has the voice and thoughts of their spouse. The central joke is what happens when a female personality is applied to Mal's workplace, while an unreconstructed man deals with house and kids. Although Mal and Jill have suffered a stroke of chance rather than a vascular incident, the play, written by a man who considered himself entirely healthy, dramatises that feeling of no longer being in control of your body and mind: the major experience of stroke-sufferers.
"Yes," says Ayckbourn. "It's a bit spooky, that. I have been able to make use of it in rehearsal. Extraordinary things happen with strokes. When your arm first returns, it's a bit uncontrollable, a bit Dr Strangelove."
When he went back to the Stephen Joseph Theatre for the first time after his illness, he shook the hand of an actress, then reached out to another well-wisher with his other hand: "Only when I felt a gentle tugging to the left did I realise that this poor actress, who was trying to get to the bar, was still held in the vice-like grip of her manic director."
If I Were You continues his fascination with "the different attitude men and women have to things", and also extending his enjoyment of games with acting and staging. He at first thought of having "two drag-acts coming on in the second half", but Liza Goddard and John Branwell will now remain in the same costumes, suggesting their transformation through voice and movement.
Doctors have warned Ayckbourn to slow down, and he insists he is trying. An associate director will be appointed to share the task of running the Scarborough theatre, and rehearsals for If I Were You are taking place at his home. The house is a converted school and one of the old classrooms, previously a playroom for his grandchildren, is now covered with the white floor-tape and bitten styrofoam cups of a theatrical event in preparation.
But, even if returning to work merely means going downstairs, illness can knock your confidence, and Ayckbourn admits: "I was very, very nervous on the first day of rehearsal. My biggest fear was that you get very, very tired, very quickly. And the doctor has warned me that, if you keep on pushing, there will be a relapse. So I'm being careful. But, really, it's just an exaggerated version of the way I directed before: very casual, lots of anecdotes. We have a chat and then do a bit."
Satisfied that he can still direct, he has not yet tested the primary part of his brain. Since February, his only professional writing has been a note for the summer/autumn 2006 programme at the Stephen Joseph, which thanks well-wishers for their gifts and concern and concludes: "I owe, in no small part, my returning health to all those loving and caring thoughts."
He knows that the true proof of his recovery will be a new play: "I think, once I've done this play, the way will be clear. The ideas keep popping up." He explains that a play emerges from shuffling in his head three separate lists: of titles, possible settings and subjects. For years, he contemplated a play about middle-class types viciously battling for dominance, but couldn't complete it until realising that this was his "cabin cruiser play", a long-held notion for floating a boat on stage. Titled Way Upstream, the play flooded the National Theatre in 1982.
The title Private Fears in Public Places was for a long time attached to a play set in an elevator or on an escalator: Ayckbourn was fascinated by the idea of using the stage vertically rather than horizontally, with characters ascending and descending. The name Private Fears in Public Places has now gone to an entirely horizontal domestic drama - a recent hit off-Broadway, a rare US success for a comic dramatist Americans have tended to rank below their own Neil Simon - but the elevator play may yet emerge, though now called something else.
The desire to try an up-and-down staging arose from the fact that the new Stephen Joseph Theatre, recently expensively renovated, has an access area beneath the boards. Ayckbourn is a great believer that plays should be what artists call site-specific: "I would hate to be commissioned by a theatre which said you could have as many settings and actors as you want. It's a hopeless freedom to have. I like to work with restrictions. My first 15 plays had only two entrances because that was what the theatre had. When we moved into a new building, I started to write plays with three entrances."
But, while accepting the physical boundaries of the stage, he is constantly trying to expand the action through structural games. Sisterly Feelings had four different possible shapes, depending on a coin tossed by the characters, while Intimate Exchanges, currently being revived in Scarborough, is a sequence of plays incorporating 18 variations. After these - and the simultaneous staging of House and Garden - I wondered if there were any other auditorium-stretching concepts Ayckbourn would like to try? "I'd like to do something opening up the whole theatre. I have this notion that the audience come in and you turn the theatre into a sort of giant hotel. The play lasts 24 hours. You give the audience a badge and they attend a conference in the main auditorium. And then a sub-plot breaks out with actors planted there and maybe there would be an affair going on in the ladies."
Apart from its run in New York, Private Fears in Public Places has just won a prize at the Venice film festival in a French movie version called Coeurs (Hearts), directed by Alain Resnais, who also turned Intimate Exchanges into the paired films Smoking/No Smoking.
Ayckbourn's perhaps surprising French connection came about because of Resnais's equally improbable affiliation with Scarborough: "In 1989, someone said to me at the theatre that they'd just seen Alain Resnais in the lobby. And I said, 'Oh, yeah. And Jean-Luc Godard is in the gents.' But I went out, and there he was."
It turned out that Resnais holidayed each year at the Yorkshire seaside in order to see Ayckbourn's plays. When the director suggested that some of these theatre pieces might form the basis for "un film de Alain Resnais", the dramatist was sceptical, but Resnais told him: "We are more similar than you think. You write films for the stage. I direct plays for the movies."
Subsequently, at Scarborough register office, with Sir Alan and Lady Ayckbourn as witnesses, Resnais married French actress Sabine Azèma, for whom, as a wedding present, a part was written in House and Garden.
The success of Private Fears in Public Places in American theatre and French cinema distracts from the fact that - in common with several of his recent pieces - the play has received no London production.
At the National, Ayckbourn was almost playwright-in-residence under Sir Peter Hall - who staged the marital classic Bedroom Farce and commissioned the dark comedy A Small Family Business - and Richard Eyre employed him to write children's Christmas shows. But, despite a meeting on Nicholas Hytner's third day in office, Ayckbourn "hasn't heard anything yet". "It's quite interesting," he says. "I wait like a debutante with a dance-card." Perhaps Hytner feels that Britain's most prolific commercial dramatist doesn't need the subsidised stages of the National - but private theatres also now seem wary of offering productions.
Asked whether he feels neglected by the West End, Ayckbourn gives a careful answer that seems designed to spare both his own feelings and those of commercial producers: "Well, I have politely declined some offers. But I think the West End has become pretty unsympathetic to the new play. I looked at the paper the other day and London was just like Broadway has become: musicals, musicals. And plays with imported movie stars who can't be heard beyond row four."
In this hard market for theatre, the only plays that can compete with song-and-dance shows are classic revivals and, even before his personal medical drama might have encouraged it, Ayckbourn was exploring his backlist. Apart from Ayckbourn's own re-examination of Intimate Exchanges, Kevin Spacey - a movie star who can project well past the fourth row - is staging The Norman Conquests at the Old Vic next year.
Spacey recently came to discuss the production and, emerging from Scarborough station, found himself facing a pub called the Old Vic. "He felt he had to go in," says Ayckbourn. "So he was sitting with his half of beer and all these crusty Yorkshire types, looking at him sideways. So he asked them why it was called the Old Vic, and they told him it was because Charles Laughton was born nearby."
As Ayckbourn has been such an advocate of new plays, is there a temptation, with revivals of his work, to tinker and begin again? "No. I rarely change anything. They are what they are. The ones I urgently need to rewrite are the ones I wouldn't want to revive, anyway. But it's odd. Because they deal primarily with human relationships, I almost never refer to contemporary events in my plays: unlike David Hare, for example. And I think the misunderstanding between men and women is just as huge now as it was then. In Intimate Exchanges, I just updated the cost of a bottle of whisky."
Even old topical references can prove inadvertently durable. A reference in Intimate Exchanges to terrorists "sitting in hotel rooms wiring up boxes" was intended when written as a reference to the IRA, but the audience now thinks of Islamic extremists.
"I was just thinking the other day," says Ayckbourn, "that I was born in 1939 and so, all my life, people I don't know have been trying to kill me. The Germans dropped bombs on my house in London and I remember my mother saying: better sleep under the stairs. Then it was the Russians, then the Irish, now another lot of terrorists. I'm starting to accept that I'm a marked man."
This sense might have been increased by an internal threat - his body's own attempt to blow him up. But Ayckbourn happily avoided this latest attempt on his life, and an hour's comic and thoughtful dialogue with him suggests everything is ready for the next stage of his recovery - which will be writing his 71st play this year.
· If I Were You opens on October 12 at the Stephen Joseph Theatre in Scarborough. Box office: 01723 370 541.
