This should really have been a case for journalist Jon Ronson. He’d have had it all cracked in 45 minutes and without the need of a mind palace, that’s for sure. In fact, with the solution involving a shadowy military project that drove its participants insane, this instalment could just as easily have been called The Men Who Stare at Dogs.
It all started promisingly enough with Sherlock in a state of nicotine withdrawal and craving something “seven per cent stronger” than tea. You see what they did there? We even got an evocative account of Henry Knight’s childhood trauma courtesy of the ever-reliable Russell Tovey, who really seemed to relish uttering everyone’s favourite line from the novel – “Mr Holmes, they were the footprints of a gigantic hound.”
The problem came around the halfway point when Holmes began to wrestle with unwanted emotional intrusion – “the grit on the lens” as Sherlock described it to John.
Now maybe he was still raw from last week’s encounter with Irene Adler but this seemed an oddly extreme reaction. It certainly wouldn’t have taken the world’s greatest consulting detective to realise that here was a man under some kind of influence. John’s “Spock” reference was spot-on: it felt that we were just minutes away from one of those sweaty, brutal Vulcan mating rituals that necessitate slashed tunics and sharpened shovels (in fact, Benedict could have practised for his new role…).
With Sherlock unravelling, the word “hallucination” should have started shining in the minds of viewers as brightly as that poor girl’s luminous rabbit. A Porton Down-style base, blatant experimentation, defensive army-types – come on, what else was the twist going to be?
Screenwriter Mark Gatiss did introduce some teasing layers of obfuscation: the inclusion of Stapleton (the story’s original antagonist) turned out to be a red herring, while Sasha Behar (formerly Coronation Street’s Mad Maya) appeared suspicious as Dr Mortimer yet was actually completely benign.
Unfortunately, the big reveal (of both hound and villain) ended up being a missed opportunity as John shot the CGI mutt and Dr Frankland stepped into a minefield that appeared to have been introduced solely for the purpose of bringing about his death.
Maybe only purists expected a slow seep into the depths of the Grimpen Mire, but this remains one of the best exits in the whole of the Conan Doyle casebook. Was it asking too much to expect some kind of 21st-century transfer?
Yet despite a slight sense of disappointment at the climax, there were some moments to savour, most notably the scene of sweet affection between Sherlock and John: “I don’t have friends. I just have one,” Holmes told his flatmate. But judging by the coda to tonight’s episode, it’s his enemies that should be of greater concern.