Welcome to the Sherlock escape room game where the entrance is hidden in plain sight

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Over the road from Shepherds Bush tube station in London, the West 12 shopping centre is the poor relation of its big-name neighbour Westfield. But that makes it the perfect place to hide the entrance to this part escape room challenge, part immersive theatre experience.

Enter West 12 and you’ll see the usual array of non-designer shops, and at the far end a big Lidl supermarket. Walk up to that and take a right and up ahead is an optician’s. It looks like any other budget optician’s in a UK shopping centre – brightly lit, shelves of glasses, laminated floors and low-cost office furniture – at first glance you’d have no idea that there was anything out of the ordinary about it.

But then you might remember Sherlock's maxim, “the art of disguise is knowing how to hide in plain sight”. And you might look a little closer. You might notice that the optician’s is called Doyle’s. You might spot that it was established in 1859. And if you were a real Arthur Conan Doyle aficionado you might know that that’s the year the Sherlock Holmes creator was born. If not, the poster in the window might give you a clue. “Your eyes are our eyes”, it reads, surely a hint that you are about to join Sherlock’s crime-solving collective The Network.

Yes, Doyle’s optician is where your journey begins, with a 30-minute immersive section in the shop itself, before you're ushered into an ante room to be briefed by a character from the show.

Then comes the first big treat for Sherlock fans, a near-perfect recreation of Sherlock and John’s 221B Baker Street flat. This is not one of the escape rooms but a chance to soak up the atmosphere of the show’s most iconic set, and take some souvenir photos by the mantelpiece or on the sofa, before a video message – one of a number recorded by the main cast, including Benedict Cumberbatch as Sherlock, Martin Freeman as John and Andrew Scott as arch-villain Moriarty – finally sends you into the game proper.

That’s where the story ends for now. When I visited for a “hard hat” tour of the place, the rest was still under construction, but the finished game will also feature a series of three separate escape rooms, running to a total of 60 minutes, and end with a debrief and a chance to wind down from the excitement with a drink or three in what sounds likely to be rather salubrious surroundings.

Details of the escape rooms themselves will remain under wraps of course but the pedigree of those behind the game bodes well. Time Run, the company who created the acclaimed escape room adventure of the same name, are responsible for the functionality while Sherlock co-creators Mark Gatiss and Steven Moffat have come up with the stories and puzzles.

“The narrative takes us to different places and we wanted to have a nice sense of scale and a change of environment," says Gatiss, "so it doesn’t all feel very wintery with the curtains drawn. That reflects what we always wanted to do with the show; it’s not a Victorian show, it’s about modern London as much as anything. So there’s a nice selection of different environments to play in.”

You’ll get more out of the game if you’re a Sherlock fan, says Moffat, but an encyclopaedic knowledge of the series is certainly not required – and aficionados of the original stories shouldn’t expect to have a huge advantage either.

“You could walk in and play the game with no knowledge of it at all," he says. "You will enjoy it more, I think, if you do, but it’s not dependent on your knowledge.

“[Basing it on a famous Sherlock Holmes story] wouldn’t work. If you go into one of the mysteries and there’s a bell rope attached to a wall, you’d think, ‘Oh, that’s The Speckled Band.’ The answer can’t be something that’s already existed for over a hundred years. That would be wrong."

"You’d exclude people who didn’t know it," agrees Gatiss, "and if anyone did know it, they’d solve it straight away. We were very keen to make sure it feels ‘gettable’. You don’t have to have seen the show or even really know Sherlock Holmes; you can still do it. Also, you don’t have to spend too long digesting back story when all you really want to do is get on with the game.

“For us, it’s going back to the very first principle of what we enjoyed about reading a Sherlock Holmes story, which was that you want to do it yourself. You want to think, ‘Can I tell from the turn-up of someone’s trousers and what’s on his hair what he does for a living?’ Clues and deduction. It’s a very natural marrying of things, and escape room games are so massively popular.

"Whether it’s a team building thing or a stag night, just pre-Christmas fun or whatever, it’s just a lovely thing. And if you can combine that with your favourite TV show then it’s a very nice night out.”

Find out more about Sherlock: The Game Is Now and buy tickets