Time Out says
The first hour of Atonement is an electric experience, during which one feels that Joe Wright (Pride and Prejudice), the film's young director, and Christopher Hampton, its screenwriter, have a clever grip on the potential of Ian McEwan's novel to inspire more than just a well-crafted adaptation and a lyrical, intelligent film in its own right. McEwan's book is about the telling of stories, about the perception of others' tales and about delivering a lie to a rapt, conditioned audience for reasons of self-preservation: a key character even pleads to be believed with the defence that she saw something happening, 'With my own eyes'. What greater appeal is there to the potential ability of cinema to twist, mould and convince us?
Wright tightly harnesses these ideas in the first, and longest, of the film's three chapters. We're in a smart country house in the late 1930s, just a few years before the war. Cecilia (Keira Knightley) has recently come down from Cambridge; Robbie (James McAvoy), her university contemporary and son of her parents' housekeeper is dabbling with landscape gardening; and her brother Leon (Patrick Kennedy) is coming to dinner with a friend, the arrogant industrialist Paul Marshall (Benedict Cumberbatch). The performances are enjoyable and spot-on: Cecilia's brittle beauty; Robbie's educated but tempered confidence; the wily camaraderie between Leon and Marshall.
There's clearly an attraction between Robbie and Cecilia, yet his connection with the servile classes and her inherited snobbery is holding Cecilia at bay. The class divide persists when Cecilia's sensible 13-year-old sister, Briony (a terrific turn from Saoirse Ronan) -- already dabbling in writing and staging plays at home -- constructs her own, deluded fiction around the goings-on between Robbie and Cecilia that see Robbie falsely branded a 'sex maniac' and rapist. As with the coming of war to Brideshead, the spell is broken, the Second World War begins and Briony, later as a young adult (Romola Garai) and, much later, as a dying novelist (Vanessa Redgrave) recalls the errors of her youth.
Far from 'unfilmable', as some have described it, McEwan's book offers real opportunities for a filmmaker to thread the perils of storytelling into an epic narrative that bursts out of the attractive claustrophobia of a rarefied world and onto the ravaged, classless beaches of Dunkirk and the fortified streets of London as Cecilia and Briony both, separately, work as nurses during the war and try to deal with their recent past. For the country-house scenes, Wright wisely makes us complicit with Briony's perception of events, yet such is the strength of the director's tactics in this chapter -- repeated scenes, messing with time, the sound of a typewriter doing its damage on the soundtrack -- that when he loosens his approach for a more traditional telling of the narrative for the rest of the film, one can't help but be disappointed.
Compared to these earlier episodes, the film's later scenes are more pedestrian and Wright becomes more prone to visual swaggery: a technically impressive but artistically questionable five-minute tracking shot of the carnage at Dunkirk; the nurses marching in formation around a hospital as lights go off above them one-by-one; the rush of water through a tube station as a character drowns -- all these grate as one feels that Wright, rather than tackling the pitfalls of storytelling instead succumbs to its audience-pleasing thrills.
A noble, well-made, superbly performed and photographed (by Seamus McGarvey) semi-failure then, but still one that shows Wright to be one of the more imaginative filmmakers of his generation, capable of winning over large audiences with daring endeavours.