If you were coming up with a list of greatest Britons, who would you have on it? Churchill, Darwin, Brunel, and Newton would appear on most. Thomas Paine and Aneurin Bevan would be more controversial but common picks. One man who deserves to be talked about in that company is Alan Turing. A wartime code breaker who cracked the “impossible” German Enigma code and who made a massive contribution to both shortening and winning the Second World War, as well as to the invention of the computer.

In Morten Tyldum’s new film he is played by Benedict Cumberbatch, amidst much awards buzz. Cumberbatch is perfect for the role. Playing a genius does mean that there are glimpses of Sherlock Holmes but it is a distinct enough, pitch-perfect performance for that not to be an issue.

The film is set in three time periods. For the most part, it concentrates on the war years and the efforts to break the code. We also see scenes from his childhood at boarding school and those surrounding his arrest for indecency and tragically early death a decade after the end of the war. It is the former that are the most compelling, and the school time scenes, are if not unnecessary, a bit repetitive.

As you would expect for such a prestigious picture, the period detail is spot on, and the script evokes the time convincingly. Aside from Cumberbatch, the supporting cast are all solid. Keira Knightley as the only female member of the team, and briefly Turing’s fiancée, seems to be living up to her early promise after her diversion into the increasingly ludicrous Pirates of the Caribbean movies. The pick, though, is Mark Strong as the MI6 agent. Admittedly he is given some of the best and funniest lines, but he is excellent nonetheless.

I have seen some comments about the film shirking away from Turing’s homosexuality. I find that strange as a whole section of the film is taken up with his fall from grace as a result of that. This is a fitting film for such an important man, funny at times but also conveying the deadly seriousness of the task at hand. It may well leave you feeling rightly angry at the shocking way he was treated in later years, but it does go some way to bringing his extraordinary achievements to a wider audience.

Rating: 9 out of 10