Benedict Cumberbatch, Keira Knightley and other co-stars braved the rain at the BFI London Film Festival opening night gala screening of their new film, The Imitation Game. The British movie tells the story of pioneering mathematician Alan Turing, who played a key role in breaking the German Enigma codes by developing a pioneering electromagnetic analyser – a "bombe" – as well as a system for statistical analysis of the ciphers to help in the codebreaking. His wartime activities led to a post in the mathematics department at Manchester University in 1948, where he worked on the Manchester Mark 1, one of the first stored-program computers. It was while he was living in Manchester that a burglary in his flat led police to suspect he was gay and – at a time when homosexuality was illegal – he was prosecuted for gross indecency. Turing accepted hormone treatment as an alternative to imprisonment, and it is generally accepted that the effects of this led to him killing himself in 1954.

His reputation, however, began to rise after Bletchley Park’s wartime work was declassified in the 1970s, culminating in an apology on behalf of the government by Gordon Brown in 2009 and a royal pardon in 2013.