If Simon Gray's publisher ever decides to undertake an annotated edition of his diaries, I am definitely putting in for the job. “This should settle my hash, this long disease my hash,” Gray writes, somewhat mysteriously, on page 15 of The Last Cigarette. Well, imagine the joy of being able to explain that this is a private reference to a speech in his play Butley (1971) about the hero's mother-in-law: “Anne's mother the mad monk settles the hash of bus-conductors, milkmen, postmen, anyone stupid enough to waste their time insulting her. ‘Oh, I settled his hash all right.'”

However, at the same time as one rashly volunteers to help Gray hereafter in any capacity whatever (“Me! Pick me!”), one can't help asking whether this effect of recruiting keen, kind-hearted readers has been a bit deliberate, not to say quite cunningly done. In his younger days, Gray was well known as a rather brutal and supercilious hash-settler himself; early plays such as Butley and Otherwise Engaged had the fascination of prize fights. Endearing himself to his audience, and eliciting its sympathy, was not Gray's priority.

Well, all this has changed. One of the many pleasures of the diaries published in his sixties - The Smoking Diaries (2004) and The Year of the Jouncer (2006) - is in observing their determined effort to redress past arrogance and present, in a highly comic manner, a shambling, limping, futilely raging and self-disgusted figure, full of honest human doubts, terrors and regrets (as well as the odd residual spot of cheer-leading white-hot contempt). In the course of events covered in The Last Cigarette, a new production of Butley is staged on Broadway, and Gray's wife, Victoria, delivers the enormous news to him that it is a misogynist play. And it is a measure of something (I wouldn't dare say what) that he not only reports the gist of their conversation, but admits that he had been “coming to something like the same thoughts myself”.

Fans of the previous books will have all their expectations rewarded. Gray writes his diary in familiar spots - at a favourite hotel in Barbados, at his homes in Suffolk and in Holland Park, and on the Greek island of Spetses, which he also calls home. As before, he often writes “to the moment”, in the manner of old epistolary novels (“We're on the tarmac at Athens airport”), and trains of thought are allowed to meander down any number of branch lines, sometimes at considerable speed, so that a telephone conversation with Peter Hall just switches track - self-consciously, but without apology - to a memory of hot dogs, then to childhood in Canada, to rationing in England and a hateful visiting French boy who complained about the food. As the train of thought slows down and crosses a low valley, he remembers his mother's love for France, then regrets that there are so few photographs of her, and as it finally slows to a stop (perhaps at Adlestrop), he asks himself, agonisingly, why he took the decision not to spend longer with her when she was dying.

There are delicious rants on the modern world, and wonderful descriptions. When British Airways gives its passengers a box of food, Gray describes the contents as “smatterings of this and that, a little roll of ham that looks like a boiled thumb, a smudge of cheese,” and so on. “Altogether like scraps left over from a reception.” The bit of sustained writing I admire most, however, is his description of the first-night party for Butley in New York, where everyone is pretending there is nothing ominous about the lack of news. Gray explains there is a kind of hope that is merely “despair delayed by an act of will” - but that he personally doesn't suffer from it. What possible positive interpretation can be put on the late arrival of the all-important New York Times review, he asks, “that the review was so intensely favourable that it had to be vetted by specialist policemen for signs of conspiracy”? Perhaps the reviewer had delayed publication because he “wanted to insert some extra compliments that had occurred to him just as the paper was going to press”?

Of course, the sense of a complete life being honestly recorded is an illusion - albeit a benign one. There is nothing in this diary about the sales of these books of his, for instance - a business that must surely have dominated his thoughts in the past five years. They have been shortlisted for awards and universally admired. There must have been a certain amount of anxiety attached, too, with deadline pressure, and so on. However, the only impact of the books recorded here is Gray's horror when he realises that people at his regular Barbados retreat have been reading the papers and now know precisely what he is up to: “I'm beginning to get the feeling, confused and I hope merely the symptom of a short-term mental disorder, that some of them are posing for my writing...”

In fact, he is just starting to think this might be true when someone comes over and punches him in the stomach. At which point, he accepts that the game is up. “It's odd to think that these are the last words I'll ever write at this table - well, it's my own fault, as are most of the things that I don't like about my life.”

Gray has been saying that this is the last book. He regards himself, at 70, as a very, very old man - which he isn't, but he plainly feels like one, beset by bereavements, hating his teetotal condition and full of the self-disgust of age. At one point he muses on the difference in meaning between “shaming” and “shameful”, and calls on “hating” and “hateful” to help him out. The choice is not insignificant. At the end of the book, he reports the discovery of a tumour on his lung (the goal of giving up smoking, of course, was never achieved). But if he wants to stop writing these diaries now, he has certainly earned the right. It seems to me that the triumph of these books is not in how a man redeems himself, but how a writer does. Gray used to write unashamedly old-fashioned plays; being remembered for them alone would of course have been sufficient. But whoever could have predicted that at the end of his career he would hit on such an artful, brilliant, personal and glitteringly postmodern way of - well - settling his own hash?

The Last Cigarette: The Smoking Diaries Volume 3 by Simon Gray
Granta £14.99 pp312

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