Atonement: book vs movie — every major difference, and the one that changes what the ending means

Ian McEwan's 2001 novel and Joe Wright's 2007 film tell the same story, in the same order, with the same architecture of lies. They part company in the last few pages, and the parting is deliberate.

Hampton's first draft ran voiceover throughout and leaned literary; Wright asked him to start again, and the second version is the one that got made. What survived the rewrite is most of the novel's structure — the 1935 heatwave at the Tallis house, the fountain, the letter, the library, the arrest, Dunkirk, the nursing, the wedding in Clapham, the flat in Balham. What did not survive is the machinery McEwan built to show you that Briony has been rewriting this for six decades.

The cuts that thin out Briony the novelist

The film has three Brionys — Saoirse Ronan at 13, Romola Garai at 18, Vanessa Redgrave at 77 — and gives each of them roughly one register. The novel gives her a paper trail.

• The Horizon rejection — In Part Three of the novel, Briony submits a novella called Two Figures by a Fountain to Cyril Connolly's magazine. The rejection letter runs for pages, is signed "CC", and is a piece of literary criticism telling her the fountain scene has no spine and needs a crime in it. It is gone from the film entirely.
• The drafts — The novel's last section is dated "London, 1999" and identifies itself as the latest of many versions, begun in 1940. The film gives Briony one book, her twenty-first.
• The research — Novel-Briony spends the morning of her 77th birthday at the Imperial War Museum returning letters from a Dunkirk veteran. The film replaces institutional legwork with a television studio.
• Luc Cornet — The dying French soldier who mistakes the trainee nurse for his fiancée survives into the film, but compressed.
• The Trials of Arabella — The play Briony writes in 1935 and never gets performed is staged by the family's children at her birthday party in the novel's final pages. The film drops the payoff.

Both versions keep the deaths and both keep the dates. Robbie dies of septicaemia at Bray-Dunes on 1 June 1940, hours before the evacuation would have taken him off. Cecilia is killed in the Balham Tube station disaster in October that year. They never see each other again after 1939.

Read more: A Pale View of Hills movie explained: the film settles what Ishiguro's novel left open for forty years

What the film builds instead

Wright's additions are visual rather than structural, and the largest of them is the Dunkirk tracking shot: roughly five and a half minutes, a quarter of a mile of beach, Seamus McGarvey shooting and Peter Robertson operating the Steadicam across a tracking vehicle, a ramp-mounted rickshaw and two stretches on foot. The production had two days and limited money for extras. Three full takes were completed, a fourth abandoned when the light went; the third is in the film.

The Tallis house is Stokesay Court in Shropshire. Redcar seafront is Dunkirk. The Grimsby Docks ice factory supplies the shelled streets, Streatham Hill stands in for Balham, and the disused Aldwych Tube station recreates the flooding. Dario Marianelli's score runs a manual typewriter through the orchestra and won the film's only Academy Award, from seven nominations.

The difference that changes the ending

In the film, Briony sits in front of a camera at BBC Television Centre, tells an interviewer she has vascular dementia, and admits on the record that the Balham reunion never happened. The confession is public, finished and broadcast.

In the novel, it is none of those things. Briony explains that she cannot publish while Paul and Lola Marshall are alive, because the libel laws would destroy her and the Marshalls have the money to use them. Lola is older than Briony and in considerably better health. The manuscript is therefore a confession nobody will read in her lifetime, filed against a death she does not control.

"The problem these fifty-nine years has been this: how can a novelist achieve atonement when, with her absolute power of deciding outcomes, she is also God?" — Briony Tallis, Atonement, 2001

Wright has framed his version as a question about the function of a happy ending, for the writer and for the audience both. McEwan's version leaves the question open and the confession unpublished, which is a different proposition: one Briony has done what she can, the other has arranged for it to be someone else's problem.

For the record: in November 2006 the New York Times reported that a passage in the nursing section echoed Lucilla Andrews's 1977 memoir No Time for Romance. McEwan had acknowledged Andrews in the novel's author's note and told The Guardian that month, "An inspiration, yes. Did I copy from another author? No." John Updike, Martin Amis, Margaret Atwood, Kazuo Ishiguro, Zadie Smith, Thomas Keneally and Thomas Pynchon all published statements in his defence.

Read more: Kate Winslet’s Sense and Sensibility is untouchable — the new one has opened at 80%