Two weeks ago, a video of Benedict Cumberbatch rattling off 11 impressions in one minute — nine of which were great — made its way around the internet, which received the feat of strength with incredulous delight. I was impressed, but underwhelmed, because I had already seen Cumberbatch pull off an impression so good, he might win an Oscar for it. Not of Alan Turing — there are no known recordings of his voice — but of Sheldon from The Big Bang Theory.
In his review of The Imitation Game, David Edelstein applauded the "captivating strangeness" of Cumberbatch's performance, saying that "The role is shaped — no surprise — to make Turing Sherlockian in his arrogance." I understand the Sherlock comparison, considering it is still the role Cumberbatch is most associated with, but I'd argue Cumberbatch's Turing doesn't have the bravado or the suaveness of Cumberbatch's Sherlock. His Turing is arrogant, but it's so awkwardly executed, it's damn near sitcomlike in its rhythm — you know, like Sheldon. Sherlock wears cockiness like a tailored trench coat. Turing wears it, as Sheldon does, like an ill-fitting Flash T-shirt over a mismatched long-sleeve T-shirt. Cumberbatch's Turing is not a Sherlockian archetype; he, like Sheldon, is a nerd (with his crossword-puzzle obsession subbed for a comic-book one).
Here is one of many examples of Cumberbatch's Sheldon-ness. If you added a laugh track, it would work as a scene in the pilot for a British remake of BBT.
There is a similarity in the timbre and rhythm of their voices, but it comes down to the roles they play in scenes. Like The Big Bang Theory, a lot of The Imitation Game is scenes where a genius treats a bunch of lesser geniuses like they're dummies. There are many scenes in which the other code-breakers ping-pong ideas back and forth, just for Turing to come over the top to say everything they're saying is stupid. Conversely, there are the scenes where the greater genius fails to comprehend the normal behavior of the lesser geniuses as they do things like flirt and tell jokes. Seriously, is that not every single Big Bang Theory scene?
This doesn't necessarily mean that Cumberbatch's performance is any less laudable. Actors channel unlikely sources for inspiration all the time, like Johnny Depp doing Keith Richards in the Pirates of the Caribbean movies. If Depp could get an Oscar nomination for that, there's no reason Cumberbatch can't get one for playing Sheldon. Hell, Jim Parsons has won four Emmys doing it.