Follow the clues with detective fiction trivia on Sherlock Holmes, Agatha Christie, hard-boiled gumshoes, and the history of mystery. From foggy London streets to locked-room puzzles and unreliable alibis, whodunits have kept readers guessing for over a century. Examine the evidence and prove your mystery knowledge is elementary.

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This loyal friend and former army doctor serves as Sherlock Holmes's assistant and the narrator of most stories.
This iconic London address is where Sherlock Holmes rents rooms from his landlady.
This Scottish physician and writer created the world's most famous detective in 1887.
Watson notes that Holmes could have been a professional musician, given his skill with this instrument he plays when thinking through cases.
Sidney Paget's illustrations made this distinctive hunting cap synonymous with Holmes's image.
Holmes claims to be the world's only practitioner of this unique profession he invented, where Scotland Yard seeks his help on difficult cases.
Holmes calls this criminal mastermind and former mathematics professor the Napoleon of Crime.
This long-suffering landlady tolerates Holmes's chemical experiments, irregular hours, and occasional gunfire indoors.