“Sexual intercourse began / In nineteen sixty-three / (Which was rather late for me)”, Philip Larkin famously lamented. They are lines whose spirit suffuses every page of Ian McEwan’s remarkable new novel.

It is July 1962, and in the honeymoon suite of a genteel hotel on the Dorset coast, Edward and Florence (22-years-old, very much in love but never having made love, to each other or anyone else) are anxiously approaching their wedding night. Creaking across the waxed oak floorboards, nervous youths in waiter’s jackets serve them dinner from a trolley: one slice each of melon tipped with a glazed cherry, plates of “long-ago roasted” beef (“his piled twice as high as hers”), bluish potatoes, starchy gravy, soft boiled vegetables. Hirondelle white wine is poured.

It might be the opening of a sardonic comedy. But readers of McEwan are likely to suspect otherwise. In his fiction, couples on holiday or honeymoon have hitherto met grisly fates: falling foul of murderous sadomasochists in Venice in The Comfort of Strangers (1981), ruinously crossing paths with feral mastiffs in the Languedoc in Black Dogs (1992). Nothing as savage as this happens in On Chesil Beach. What does is infinitely more affecting.

McEwan’s last book, Saturday (2005), made prominent use of Dover Beach, Matthew Arnold’s poem in which lovers in a room overlooking the English Channel are silhouetted against Victorian preoccupations. On Chesil Beach, also portraying a couple in a room overlooking the English Channel, is likewise concerned with individuals’ relationship to their times. Until the psychedelic tsunami of the 1960s swept it all aside, you’re quickly reminded, the buttoned-up ethos of the 1950s persisted into the start of the next decade. Restraint – verbal, physical, emotional – is second nature to Edward and Florence. Reticence (things unspoken influence what happens in the honeymoon suite in several ways) predominates. Cramped erotic etiquettes have chaperoned their courtship. “Sudden moves or radical suggestions on his part could undo months of good work” – as with an ill-judged bid to increase intimacy during a viewing of A Taste of Honey.

Now a four-poster with a taut white coverlet awaits them in the next room. Almost choking with eagerness, Edward worries about overexcitability and inexperience. Practically nauseous with dread, it emerges, Florence is shaken by more deep-rooted panic. In this heightened atmosphere, things take on nearly hallucinatory suggestiveness. Dangling from his waistband when he gets up from the dinner table, Edward’s napkin suddenly looks like a loincloth to him. Plants with swollen stalks and thick-veined leaves loom through the sea mist in the hotel garden. Breezes waft in “an enticement, a salty scent of oxygen and open space”.

Focusing with hyper-acute attentiveness on just two hours or so (Saturday, with its one-day time-span, looks baggy in comparison), the book tightens even further McEwan’s consummate powers of close up. No nuance of body language, fluctuation of mood, tiny fluttering muscle or hair-trigger stirring of sexual arousal is missed. Every gradation of the couple’s external politeness and internal perturbation is registered.

Clean of sprawl and clutter – not a word, incident or image seems slackly placed – the book never hardens into the schematic. Where McEwan’s earliest handlings of one of his dominant themes – attempts to attain and sustain loving partnerships – often seemed diagrams of male and female stereotypes, everything here is alive with human complexity. Surely seeing off for good the myth that he is a “cold” writer, Edward and Florence are intensely likeable, believable people into whose personalities and predicaments a wealth of imaginative sympathy has welled.

Another key McEwan motif is also to the fore: human vulnerability. Menace has always stalked his fiction. His characters are constantly at the mercy of freakish misfortune or malevolence. In one brilliantly handled flashback here a pregnant young wife standing on a wintry railway platform in 1944 with her shopping bag of “meagre, wartime Christmas presents” is struck by a violently flung open, heavy carriage door and lastingly brain damaged. More insidious damage done by decency is what the novel most extensively explores. How kindness, generosity, consideration and responsibility can be drawbacks are uncovered with the same finesse that McEwan brings to his displays of how a slight misreading of signals, an unlucky pause or overhastiness, an ill-chosen word or inflection can provoke estrangement.

Irony flickers semi-satirically over scenes from Edward and Florence’s past: the CND gathering where they meet amid piles of pamphlets warning that Oxford will be “unapproachable for 10,000 years” after a hit by a hydrogen bomb; the up-to-the-minute lifestyle he encounters in her parents’ house – walls “exotically painted white”, varnished cork tiles, disconcerting new foodstuffs such as yoghurt (“a glamorous substance” he has previously comes across only in a James Bond novel), anchovies, freshly ground pepper and bread without butter. Gradually, it modulates into something deeper.

Crisp vignettes deftly highlight contrasts in the couple’s backgrounds: her father is an assertive businessman, his a self-sacrificing schoolteacher; her mother is a spiky, intellectually combative don, his at a far remove from this. Everywhere unshowy symmetries, foreshadowings and intimations elegantly shape the book. Dialogue is pitch-perfect: “Darling . .. Could you bear to delay your screeching until after tea?” Florence’s mother wails as her daughter, an accomplished violinist, practises. McEwan’s supple, streamlined prose is exhilaratingly full of little, apt shocks of phrasing: Edward’s abstinence is “bearing down hard on his body’s young chemistry”; unable to share Florence’s love of classical music (he prefers blues), he chafes at the “prim agitation” of a Mozart quintet.

A history graduate, Edward has learnt how people can be victims of the zeitgeist. A music graduate, Florence knows the difficulties of achieving harmony. Subtle, witty, rueful and sometimes heartrending, On Chesil Beach coalesces these perceptions into a novel that is a master feat of concentration in both senses of the word.

ON CHESIL BEACH by Ian McEwan

Cape £12.99 pp169

Available at the Sunday Times Books First price of £11.69 (inc p&p) on 0870 165 8585

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