The Daffodil Mystery is a 1920 thriller novel by the British writer Edgar Wallace.

It features the detective Jack Tarling and his Chinese assistant Ling Chu.

Richard Horatio Edgar Wallace (1875 - 1932) was an English writer.

Wallace was such a prolific writer that one of his publishers claimed that a quarter of all books in England were written by him. As well as journalism, Wallace wrote screen plays, poetry, historical non-fiction, 18 stage plays, 957 short stories, and over 170 novels.