The Sign of Four, by A. Conan Doyle
This story begins with Dr. Watson advising Sherlock Holmes against dabbling with drugs because of the long-term dangers. Holmes observes a watch and deduces the habits of the previous owner. Miss Mary Morstan visits with her problem. Her father disappeared ten years earlier. For the last six years she received a large pearl in the mail. Now she received a letter telling her she was wronged and asking for a meeting. Holmes and Watson will accompany her. Their carriage arrives at a house in a new terrace. They meet Thaddeus Sholto, one of the sons of Major Sholto, the best friend of Mary Morstan's father Captain Sholto. Thaddeus tells why what he knows about the story. His brother Bartholomew discovered the hidden treasure. When they arrive they find Bartholomew murdered in a locked room and the treasure missing! The police are called. They arrest Thaddeus and the servants as accomplices.
Sherlock Holmes borrowed a dog to follow the scent of the small man who stepped in creosote. They follow the scent to the water's edge; they look around and find information. Holmes sends the Baker Street Irregulars to search for the missing steam launch. Holmes himself locates the `Aurora', and the police launch later chases it downstream in a wild chase. Holmes and Watson shoot the Andaman islander, then Jonathan Small is captured with the treasure chest. Watson gained a treasure (Chapter 11). Small tells about the Agra treasure from the time of the India Mutiny, and has the last laugh (Chapter 12).
The story about the Agra fort and the mutiny shows the attitudes of the English public. The English conquered India for its loot, just as in other wars. But the Four decided to enrich themselves and follow the example set by the royal rulers, English or Indian. A double-dealing rajah straddled the conflict and split his assets; it failed because of others who took advantage of their position. But their plan failed because of an unforeseen watcher. The Four who killed for riches were swindled out of their fortune by a clever liar who took advantage of his position. Was Doyle mocking the English system of purchased offices in his story of Sholto and Morstan?