With his Ulster, the literary Holmes wore a cravat. Rathbone’s colorful silk scarves look almost feminine today, but they harmonized with 1930s fashions (think Fred Astaire). In Guy Ritchie’s steampunk-inspired Sherlock Holmes movies, Robert Downey Jr.’s flashy ascots are the only recognizably Holmesian aspect of his costumes, even if they seem more appropriate to circa 2008 Brooklyn than Victorian London. Cumberbatch’s blue-gray scarf functions as an extension of his coat (and eyes).

It was Paget who introduced the deerstalker, mentioned nowhere in Conan Doyle’s writings. (Holmes never uttered “Elementary, my dear Watson!” either.) As its name implies, it was a hunting garment, suitable for outdoor pursuits. Paget’s Holmes wore it in the country, never in London. However, Rathbone and subsequent Holmeses wore it everywhere, including indoors. As a trope, the deerstalker improved upon the generic “ear-flapped travelling-cap” Conan Doyle gave his hero. “Holmes never hunted,” exhibition curator Alex Werner reminds us. “But Conan Doyle used the metaphor of hunting to express Holmes’s pursuit of the truth.” Though the deerstalker is no longer a staple of the English gentleman’s wardrobe, it makes an ironic appearance in Sherlock; Cumberbatch impulsively dons one to hide his face from the paparazzi, only to have it become his trademark. (His humiliating nom de tabloid is “Hat Detective.”) Downey, however, wore a fedora, in keeping with his Brooklyn hipster interpretation.