The Museum of London recently debuted Sherlock Holmes: The Man Who Never Lived and Will Never Die, a major exhibition devoted the fictional detective and the real city he inhabited. The items on display include a rare manuscript of Edgar Allan Poe’s The Murders in Rue Morgue—a key influence on Holmes’s creator, Arthur Conan Doyle—and a portrait of Conan Doyle never before seen in public. But alongside these one-of-a-kind historical treasures, visitors will find two curiously modern artifacts: the coat and dressing gown worn by Benedict Cumberbatch in Sherlock, the BBC’s 21st-century reboot of the Holmes stories.

While these costumes are obvious bait for fanboys (and fangirls) who might not be clued into the Victorian literary sensation behind the modern-day television sensation, they also serve as a reminder that Holmes’s fashion choices, from page to screen, have always launched real-world trends. In Conan Doyle’s lifetime, Holmes’s name and likeness were used to advertise pipes and shirts as well as tea, toffee, and mouthwash. More recently, Esquire, FHM, and GQ have advised readers on how to get the Sherlock look. The exhibition provides a retrospective of Sherlockian style, investigating how it has evolved while retaining its instantly recognizable Victorian fashion DNA. The museum even commissioned a Scottish textile mill to create a signature tweed in Holmes’s honor, and a concurrent show features fashion photographer Kasia Wozniak’s prints made using a 1890 field camera.