McEwan is engrossed not merely by damage but its aftermath.

Taking you into the world of a country house situated amid handsomely landscaped grounds, Atonement opens with a leisurely expansiveness unexpected from Ian McEwan. It is the hottest day of the hot summer of 1935, and 13-year-old Briony Tallis, feverish with literary ambition, has just written a play for family performance. As she tinkers with this juvenile production, though, the cast for a grimmer drama (in which Briony will be both author and actor) assemble around her. Prominent among them are her precocious cousin Lola, not yet 16; her brother and his guest, a thrusty young tycoon; her older sister and Robbie Turner, the son of one of their domestics, whose recent undergraduate career the family has funded. With Mr Tallis absent as usual in Whitehall, control of this fateful house party is in the ineffectual hands of invalid-ish Mrs Tallis.

It might almost be a novel by Elizabeth Bowen. From its mock-gothic facade to its artificial lake and island with an imitation Greek temple, the big house and its estate are rendered in confident detail. Light effects are luminously captured: the "filtered orange glow" of the sultry evening sky hanging over the park, the "soupy yellow glow" seeping through fake parchment lampshades. In keeping with the 1930s fictional ambience, too, the influence of Virginia Woolf is constantly perceptible: the narrative flows in and out of differing consciousnesses; a disastrous roast meat dinner fed to sweltering guests parodies the triumphant serving up of boeuf en daube in To the Lighthouse.

Eschewing the technique he often favours of starting a novel with a shock (the abducting of a child, a fall from a helium balloon), McEwan here opts for a slow, suffocating build-up of tension. Elements potent in his earlier fiction - premature initiations into adulthood, sexual turbulence, ranklings of class resentment -coalesce to cause a tragedy. As always, he is engrossed not merely by damage but its aftermath. Moving ahead to 1940, then to 1999, he follows the lifelong repercussions of an outrage. But the way in which he does so -making use of a narrative as full of not-to-be-given-away twists as any virtuoso detective story -is a new development.

Of love, war and guilt

Atonement, the big-screen version of Ian McEwan’s wartime epic, is being hailed as the best British film for years

BACKGROUND

• Where truth and fiction meet

• Atonement by Ian McEwan

• The TLS on Atonement

• Atonement by Ian McEwan

• Ken Russell on the adaptation trap

Related Internet Links

• Read more out about the film Atonement

• Discover the book behind the must-see film

It initially seems puzzling, for instance, that his book's next two sections turn from violence within a house party to panoramas of wider devastation. Only glancingly anticipated in the 1935 scenes (a casual joke about stroppy Mr Hitler, family boredom at Mr Tallis's work in "Eventuality Planning" for civilian protection and mass-evacuation), war becomes central. McEwan accompanies Robbie, exhausted and with a shrapnel wound in his chest, across northern France to the Dunkirk beaches, then jumps back over the Channel to watch Briony, guilt-ridden at her role in earlier events, training as a nurse in London in the eerie lull before the Blitz.

Both sections are immeasurably the most powerful that McEwan, already a master of narrative suspense and horror, has ever written. As Robbie limps past surreal tableaux of defeat -Allied troops smashing their vehicles and armaments before retreat, French cavalry ceremonially slaughtering their horses, padres doing their bit by incinerating Bibles -he is rocked by near miss bomb blasts and strafed by machine-gun fire from Stukas. The hospital-ward sequences uncover hideous injuries with unflinching, delicate precision. It would be a very hardened reader who could turn these pages without being harrowed and moved. But, maturely modulated and nuanced, the novel doesn't restrict itself to intense emotion. A ghastly account of bone-weary nurses struggling round the clock to staunch the agonies of terribly mutilated refugees from Dunkirk is immediately followed by a preening letter ("there is much to do in this office") from Cyril Connolly to Briony about a novella she has submitted to his magazine. Typifying McEwan's refusal to simplify or caricature, this self-importance goes along with real acumen. The critical comments he fictionally attributes to Connolly are penetratingly shrewd.

Subtle as well as powerful, adeptly encompassing comedy as well as atrocity, Atonement is a richly intricate book. Unshowy symmetries and patterns underlie its emotional force and psychological compulsion. An assault takes place outside a mock Greek temple; later, a retributory wedding occurs in a church resembling one. Briony's childish playlet ironically prefigures later adult scenarios. As a novelist, she shares both her father's concern with "Eventuality Planning" and her locksmith grandfather's fascination with making things fit neatly and securely together.

Literary allusions interfuse the book. One character reads Clarissa, Richardson's tale of rape and attempted amends. In a college production of Twelfth Night, Robbie has played Malvolio, the man from below stairs whose aspirations are cruelly thwarted. The novel's epigraph comes from Northanger Abbey, Jane Austen's comedy of misplaced accusations that lead to shame; its final pages mention that the country house is now a hotel called Tilney's (the name of Northanger Abbey's occupants). Elsewhere, faithful to the 1930s decor, references to TSEliot, DHLawrence and the like proliferate.

All of this accords with McEwan's main subject. Although his novel graphically depicts the horrors of war, it is the dangers of the literary imagination that it looks at most persistingly. The instinct for order (so important in the army, Robbie finds; so beneficial in the hospital, Briony discovers) proves of more ambiguous effect when the artistic temperament impinges on life's confusions. Throughout 60 years as a writer, Briony seeks to rectify a "crime" she perpetrated in 1935 because of the impulsions that later made her a distinguished novelist: a desire to tidy up actuality into satisfying forms, a readiness to pry into privacies, a willingness to dramatise, a need for attention and approval. Boldly, McEwan's closing pages (after he has used just three words to pivot everything into a new perspective) leave you unsure whether her final attempt at atonement is an act of restitution or a last instance of self-interested manipulation. Whatever equivocations linger around Briony's behaviour, though, there's no doubt about McEwan's superb achievement in this book, which combines a magnificent display of the powers of the imagination with a probing exploration of them.

ATONEMENT by Ian McEwan

Cape. Pounds 16.99 pp375.

Available at the Sunday Times Books Direct £14.99 plus 99p p&p on 0870 165 8585

Times Recommends

• The 100 Best Books of the Decade
• The Times picks the 50 best paperbacks of 2009
• The conversation: James Ellroy