As Sherlock returns to our screens, here are 10 curious things you might not have known about the BBC series:
1. Holmes and Watson are good enough to eat
Speedy's Cafe, the sandwich emporium frequented by Holmes and Watson in the series, is a real café on Gower Street, near Euston - the BBC's stand-in for 221b Baker Street. The fans who flock there from all over the world can now enjoy specially created Sherlock-themed snacks, specifically the Sherlock wrap or the Watson Wrap.
2. Despite China's best efforts, Sherlock isn't gay
As amply demonstrated by the kisses in season three's first episode, The Empty Hearse, Steven Moffat and Mark Gatiss have always enjoyed flirting with the ambiguity of Sherlock's sexuality. "Everyone recruited him to their perspective, their interpretation," Benedict Cumberbatch once said when asked about Holmes's sex life. "I've had asexuals come up to me and thank me for representing asexuals." But they're mistaken, according to Moffat: "There's no indication in the original stories that Holmes was asexual or gay," he told The Guardian. None of which has stopped millions of Chinese fans from adopting Sherlock as a gay icon, with a vast archive of literature dedicated to his romantic exploits with Watson.
3. His pen-catching skills are beyond reproach
A scene in The Blind Banker shows John throwing a pen to Sherlock, who catches it without even looking at it. Cumberbatch made the catch on the first take (using a mirror so he could see it coming), but the cameraman was too slow and missed it. He got it again on the third.
4. '221b Baker Street' actually looks like this
The 370 sq ft one-bedroom flat above Speedy's Cafe, which is in fact about a mile away from Baker Street but doubles as Sherlock's home for exterior shots, was available for rent in early 2012 for the price of £330 a week.
5. Sherlock's staircase would please purists