Benedict Cumberbatch and Keira Knightley's Imitation Game romance labelled inaccurate

Cumberbatch plays the wartime codebreaker and computer scientist opposite Knightley as parson's daughter Joan Clarke. The pair were briefly engaged during their time working at Bletchley Park. But while Knightley is known for her glamorous film star looks, Turing's niece, Inagh Payne, has recalled his one-time fiancé as "rather plain."

Payne goes on to describe a woman who was "very nice, bright and a good friend to Alan" and says she reacted well when Turing revealed that he was gay. "When he told her about how he was she accepted it, didn't make a scene or anything like that," Payne told The Mail on Sunday.

But when it came to the film's portrayal of the pair's relationship, Payne had some grievances to air, stating, "I think they might be trying to romanticise it. It makes me a bit mad. You want the film to show it as it was, not a lot of nonsense."

Turing was a computer science pioneer and, following his wartime codebreaking work, was responsible for designing the early computer ACE. In 1952 he was prosecuted for his homosexuality, convicted of gross indecency and underwent "chemical castration" – a female hormone treatment – in order to avoid imprisonment. He committed suicide two years later, aged 41, and was issued a posthumous public apology in 2012 by Prime Minister Gordon Brown.

The Imitation Game – which stars Cumberbatch and Knightley alongside Matthew Goode, Rory Kinnear and Allen Leech – concluded filming in England last week and is set for release in 2014, sixty years after Turing's untimely death.

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