La Marque Des Quatre, published in 1896 by Arthur Conan Doyle, is a detective novel featuring Sherlock Holmes and Dr. Watson. The story revolves around Miss Mary Morstan, who seeks their help in uncovering the mystery of her missing father, the annual delivery of rare pearls, and a hidden treasure linked to Indian soldiers. This novel is notable for its exploration of Holmes's deductive methods and the introduction of significant themes such as loyalty and greed.
