Although many of his stories involve crimes or contain some elements of mystery, O. Henry never actually wrote detective fiction of the "whodunit" or puzzle-solver variety. In "The Adventures of Shamrock Jolnes", he spoofs the "marvelous powers of observation and deduction" displayed by the great detective Sherlock Holmes in Sir Arthur Conan Doyle's famous mystery series. The character of Shamrock Jolnes also appears in the short stories "The Sleuths" and "The Detective Detector".