So does director Morten (Headhunters) Tyldum drop the ball as he approaches the try line? Does he miss an open goal from two yards out? Not a bit of it. This is an absorbing and moving film, even for those of us already who know the basic story from Hugh Whitemore's hit play Breaking The Code.
Turing, in case aren't aware, was the geek who invented the computer in the course of trying to decrypt the Nazi's military communication code during World War Two. His work at the secret Bletchley Park intelligence centre is reckoned to have brought the conflict to an end two years early, and as a result saved million of lives.
Heroes didn't often look and act like this though. Cumberbatch, though attractive, is no matinee idol, and his odd, twitchy appearance underlines the fact that Turing was always an outsider - painfully aloof from his fellow human beings, partly on account of his freakish Maths skills, partly because he couldn't read the unspoken signals through which we all (or at least most of us) communicate. Today, he'd probably have been defined as autistic - then, he was just seen as odd; a cold fish.
Turing's lonerish tendencies were exacerbated by the fact that - in the idiom of the day - he was a "poofter". Homosexuality was illegal and thus a weak point that others could - and did - exploit.
While clearly sympathetic, Tyldum never shies away from the fact that his main man frequently came across as a heartless, arrogant bastard with a remarkable talent for pissing off his comrades. Yet, he also provides a welcome escape route for Joan (Knightly, superb) another maths genius who faces suburban strangulation at the hands of her parents until Turing comes along as an unlikely saviour.
Graham Moore's screenplay - based on Alan Hodges biography rather than Whitemore's drama - throws us a few juicy titbits too, including an intriguing Soviet spy sub-plot, with Mark Strong especially impressive as a conniving MI6 officer.
In truth there's rarely a dud note here. Turing, disgraced in his lifetime, is now restored to his rightful heroic status - and his full, flawed humanity.