The Sherlock Holmes hat is one of the most identifiable aspects of the fictional detective yet there is not a single mention of the word ‘deerstalker’ in any of Arthur Conan Doyle’s stories or novels. This is unsurprising since the hat was traditionally worn in rural settings, especially for hunting as its name suggests, and the urban detective would have little need for a deerstalker in Victorian London. Yet the hat has become characteristic of Sherlock Holmes and, more broadly, any kind of sleuthing.