In the original Sherlock Holmes canon, Holmes plays the violin.
Holmes uses music both as a serious artistic interest and as a way to occupy his mind between investigations. Watson describes him playing for long periods, sometimes producing beautiful music and sometimes experimenting in ways that test his companion’s patience.
The violin also reflects Holmes’s unusual combination of discipline and imagination. His analytical work depends on concentration, but he is not portrayed as a narrowly mechanical thinker. Music provides an outlet for moods and ideas that do not fit ordinary conversation.
Adaptations often emphasize this trait, although details vary between versions. Holmes is sometimes shown composing, improvising, or playing dramatically while thinking through a case. The instrument should not be confused with the violinist’s role in “The Red-Headed League” or with other musical clues appearing in individual stories; the recurring instrument associated with Holmes himself is the violin.