Good news for Sherlock Holmes fans! You might have to wait until New Year's Day to see the 'Sherlock' Christmas special, but you can now get your fix of London's favourite detective for real with HiddenCity's new cryptic trail around the city. The mastermind behind the challenge is Sherlock Holmes’ arch rival, Professor Moriarty, who will send clues to participants via text message. Each clue will guide you to a location and then you'll be asked a question about your surroundings. If you answer it correctly, you'll be sent the next clue.
The immersive treasure hunt kicks off with a briefing at the Royal Institute of British Architects and, if you're successful, you should end up at Moriarty's London safehouse. The game should take between 2-4 hours, with locations including an architecture exhibition, a Georgian pub and a Mayfair townhouse containing 15th century art. So gather up a group of your smartest pals, charge up your phone don't forget to don that deerstalker hat.
Starting point: Royal Institute of British Architects, 66 Portland Place, W1B 1AD. 2 Dec 2015 - 31 March 2016.