Screenwriter: Christopher Hampton

Distrib/release date: Focus Features/Dec. 7

Adapted from: Bestselling novel by Ian McEwan

Storyline: In a stately country home in pre-WWII Britain, a little girl’s report of what she saw — or thinks she saw, or wishes she saw — changes the destinies of three people through the war years and beyond.

About the script: “In a way, the drama of childhood is the primary drama of everyone’s life. We’re always interested in the detail that distinguishes one childhood from another, because everybody understands the givens of the traumas that could mark you for life,” Hampton says. “And it’s particularly suited to the cinema, where you can have great performances from children — not so easy in the theater.”

Biggest challenge: “How to deal with the ending,” Hampton says. “The difficulty lay in judging how and what to convey in the short epilogue where the old writer considers what she’s done in her life and her writing.”

Breakthrough idea: “To take out the voiceover. It’s so logical that you’d have a voiceover, since the book is a writer in old age looking back over her life, and you alert the audience there’s some overview going on,” Hampton says. “If you take that out, you then have to dramatize all the things you could simply have told the audience and you give yourself a lot of problems. But the payoff is, when you get to the end, it’s a real surprise. (Director) Joe (Wright) wanted to try it, because he was so afraid of making a ‘literary’ film, and I was totally supportive of that.”

Choice line: Regarding the broken antique porcelain vase that starts all the trouble, Hampton observes, “Cecilia (Keira Knightley) says, ‘You idiot, that’s the most valuable thing we own,’ which is in the book. And I have Robbie (James McAvoy) say, ‘Not now it isn’t.’ That’s a tiny example of the fun you can have when adapting a book to the screen.”

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