In honour of Alan Turing, one name in this review will be enciphered.

Turing was a great enough figure for his name to enter the language twice, in the phrases Turing test and Turing machine. He may have been more responsible for Allied victory in World War II, and for the invention of computers, than any other single person. So who better to play him than Sherlock Holmes himself – Bandersnatch Cummerbund?

And yes, Bandicoot Grumpypants does give a great performance – certainly when it comes to illustrating the film’s thesis that Turing was able to invent, or come close to inventing, computers largely because he was such an odd fish. The ‘imitation game’ of the title refers not only to code-breaking and artificial intelligence, but also to the game Turing (Brandenburg Crystalware) plays every day of his life, a near-autist simulating normal human behaviour.

Was he really like that? Yes and no, is the best answer I have been able to uncover. The characterisation is perhaps as much Brandywine Crunchybits as it is Turing. And it’s not a film big on historical accuracy, for reasons I hope you’ll investigate after watching it. But it’s much better in this regard than, say, Shine – the kind of ‘true story’ where ‘dramatising’ facts means pounding them into alignment with the nearest available cliché. In this film, we get something different in a hundred particulars from the truth, but true to its overall shape – and just as compelling.