Atonement

Meet the fragrant Cecilia Tallis (Keira Knightley), eldest daughter of a well-to-do Surrey family. Just out of college, her whole life ahead of her. Perhaps the odd summer romance on the cards. All being well, of course... Photograph: PR

But wait! Here comes trouble in the puckish form of little Briony Tallis (Saoirse Ronan). Turns out that Briony fancies herself as a budding playwright, a spinner of tales. And you know what they say about writers: they'll make up just about anything. Photograph: PR

The heat is rising, the passions stirring. Could it be that Cecilia and Briony both have their eyes on the same quarry? Photograph: PR

... and could this be the quarry? Surely not Robbie (James McAvoy), the humble housekeeper's son; below-stairs help in all but name, even if he has been sent through university on Tallis family money. Photograph: PR

In the meantime, Cecilia swans about the estate in luscious green, perhaps symbolising her budding sexuality and a certain naivety of nature. Or maybe that she is seasick. Photograph: PR

Cecilia and Robbie dream of lighting out to a little guest house on the coast. They will frolic in the ocean by day, and curl up in front of an open-fire by night. Is this but an idle fantasy? Photograph: PR

Instead, Robbie runs afoul of Briony. She spies him from a window and barely understands what's going on. She reads a letter that was not meant for her (or indeed for anyone). Thus little Briony becomes an angel of vengeance. Photograph: PR

And this, essentially, is what Briony sees from the window. Cecilia and Robbie are fighting. A precious ornament is broken. Come sundown, they're lives will be shattered too. Photograph: PR

Fast-forward a few years. Robbie is again fighting, but not with Cecilia. He's off to the beaches of Dunkirk, tainted by disgrace, bloodied by battle. And yes, still pining for the love he left behind. Photograph: PR

And here she is: the love he left behind. Now stationed at a Stockwell bedsit and taking solace from cigarettes. Still looking good on it, though. Photograph: PR

Through the poppy fields comes Robbie. He wants to sail back across the Channel. He wants to be with Cecilia. Looks like we might be set for a happy reunion ... Photograph: PR

... assuming that the meddling Briony can be kept out of the equation. To be fair, Briony has grown up a little since that dark summer of 1935 (and is now played by a different actor, Romola Garai). She is on a mission to make amends, working as a nurse and plotting to reunite the separated lovers. Photograph: PR

And here's Briony older still (and played by yet another actor, Vanessa Redgrave). Did it all turn out OK in the end? Perhaps only she can say for certain. Photograph: PR

So that's Atonement in a nutshell. A tale of forbidden love, childhood transgressions and the pain of separation. A tale of summer gatherings and wartime heroics. A tale of luscious green dresses and sneaky cigarettes. All this and a happy ending - of sorts. Photograph: PR