Abstract In the past decade, numerous film and television adaptations of Sir Arthur Conan Doyle’s Sherlock Holmes detective stories have inspired fans across the world to form vibrant communities devoted to creating Sherlockian fiction, art and music. These fans join a lineage of fandom as old as Doyle’s stories themselves, a lineage within which the interpretation of music within Doyle’s original stories, as well as performing Sherlock-related songs, constituted important acts of fandom. Through examining archival records of Sherlockian correspondence, publications and recordings as well as the textual, visual and audio-visual creations of online fan communities, I analyse the musical representation in Doyle’s original stories, and then document how Sherlockians from the nineteenth century to the present have integrated music into their fan activities. Expanding on the work of Small, I suggest that Sherlock Holmes fans engage not only in live music-making activities but also in what I term textual musicking – the fictional interpretation of canonical diegetic music in the written word. Finally, I identify how historical shifts in musical fandom embody and reflect a more fundamental recent shift in perception of the Sherlockian textual canon, but also what it means to be a Sherlock fan.