From the Shirtpunch.com's interview with the artist:
"Question: What inspired this design?
Answer: The World's Greatest Detective of course. I've been a massive fan of Arthur Conan Doyle's Baker Street dwelling sleuth for as long as I can remember. I'm a fan of all sorts of Sherlock reimaginings, but the original stories, known as The Canon, are my favourite and the titles of them are all included in this design. I got the idea at Baker Street station while riding the London tube."
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