Maroussia was only a marginal figure, though the rumours about her health proved to be portentous. In the new novel, two old friends book tickets to see her buried to the waist in Samuel Beckett’s Happy Days. It turns out to be a farewell performance in the bleakest sense. Once the curtain falls she sends a few final emails before taking a fatal overdose: “It will serve Beckett right. She has served him well and loyally and she deserves a grand finale at his expense. He has set it up for her.”

Francesca Stubbs is furious with herself for wasting what seems to be a pointless and uncomfortable evening in the theatre. But she is horribly aware that Beckett’s awful tragedy of stasis and decrepitude could soon become her own. Fran is “already too old to die young and too old to avoid bunions and arthritis, moles and blebs, weakening wrists, incipient but not yet treatable cataracts and encroaching weariness”.

She staves off retirement by traversing the motorways of Britain as an inspector of care homes inhabited by clients only slightly more advanced in years than herself. Her oldest friend Josephine, meanwhile, is a retired academic who has opted to live in faux-collegiate sheltered accommodation. “Although in excellent health, [Josephine] has met Old Age halfway and is determined to make friends with her. La Vieillesse, that is what she sometimes calls Old Age, after the title of a terrifying book on the subject by Simone de Beauvoir.”

De Beauvoir wrote her classic study of the ageing process in 1970, in terms that now appear to be prophetic: “The paradox of our time is that the aged enjoy better health than they used to and that they remain ‘young’ longer. This makes their idleness all the harder to bear. Those who live on must be given some reason for living: mere survival is worse than death.”

Drabble’s novel can perhaps best be understood as a fictional meditation hovering between the twin poles of de Beauvoir’s essay and Beckett’s play; in terms of conventional narrative development, very little happens. Fran checks into budget hotels up and down the country in order to inspect failing institutions whose inhabitants are more often than not left “softly wandering in their wits”. Josephine teaches poetry to an adult education group and works on her tapestry, while the rest of the novel concerns the manner in which their wider circle of friends and acquaintances deal, or fail to deal, with the indignities and infirmity of old age.

The compensation for the reader is that these characters are brilliantly drawn. Fran’s industry is offset by the sedentary lifestyle of her ex-husband Claude, a retired surgeon who sits among the plump cushions of his Kensington mansion ingesting self-prescribed narcotics and listening to Maria Callas. Yet even Claude’s complacency pales in comparison to the titanic self-centredness of Sir Bennett Carpenter, a grand antiquarian caught in negative equity on a paradisal Canary island that seems slightly less paradisal once he suffers a fall. The twee environs of his retirement haven are summed up by the history of the islands he intends to write: “There had been betrayals and dispossessions, but they had been small in scale. The Canaries did not swim with spilt blood. Their dried mummies were very ancient and very dry.”

Yet beneath the apparently placid surface, Drabble’s novel seethes with apocalyptic intent. The low-magnitude earthquake that shakes Sir Bennett off his feet is a portent of the volcanic activity beneath the north Atlantic that could yet have devastating consequences. The influx of Moroccan asylum seekers to the Canary Islands is highlighted as one of the least reported of European refugee routes. In either case, the narrative is loaded with dire predictions of “the dark flood” approaching.

It would all be a bit much to take, were it not for the stoicism of Fran herself, a woman who chooses to live in a dodgy north London council block, secretly rather likes dining in Premier Inns and cannot refrain from watering pot plants in airport lounges and lavatories. It’s hard to argue with her assessment of her job as “a bit of a downer” – and the same might be said of the novel itself. But you can’t help feeling uplifted by her righteous indignation about the claim that the majority of us can now expect to spend the last six years of our lives suffering prolonged ill health: “Fran found this statistic, true or false, infuriating. Longevity has f***ed up our pensions, our work-life balance, our health services, our housing, our happiness. It’s f***ed up old age itself.”