The Sign of Four by Arthur Conan Doyle Summary

The Sign of the Four is a detective novel following Sherlock Holmes and Dr. Watson as they investigate the disappearance of Captain Morstan and a stolen treasure tied to British colonial India. Themes of greed, betrayal, and imperial guilt unfold through a maze of cryptic clues, murders, and a secret pact among four convicts. The story introduces Watson’s future wife, Mary Morstan, as a central client.

Fans of classic mystery fiction and Victorian-era detective stories will enjoy this novel. It’s ideal for readers interested in Sherlock Holmes’ deductive methods, colonial-era narratives, or Arthur Conan Doyle’s exploration of morality. Educators teaching 19th-century literature or British imperialism may also find it valuable.

The phrase refers to a pact between four men—Jonathan Small, Mahomet Singh, Abdullah Khan, and Dost Akbar—who discovered a treasure during the 1857 Indian Rebellion. Their “sign” later becomes a marker of betrayal, as the treasure’s theft drives the novel’s murders and conspiracies. The symbol also represents the moral decay caused by greed.

The novel critiques imperialism through its portrayal of stolen Indian treasures and the ethical failures of British officers like Major Sholto. Characters’ greed for the Agra treasure—a product of colonial exploitation—fuels the plot’s violence, highlighting the corrupting influence of imperial power.

Jonathan Small is the story’s antagonist, a former soldier and member of the “Four” who seeks revenge after being double-crossed over the Agra treasure. His wooden leg and partnership with Tonga, an Indigenous Andaman Islander, make him a memorable villain. Small’s confession reveals the toll of colonial greed and vengeance.

The Agra treasure—a chest of jewels looted during the Indian Rebellion—drives the novel’s conflicts. Its theft by Major Sholto and Captain Morstan triggers decades of guilt, murder, and pursuit. The treasure’s eventual loss in the Thames River symbolizes the futility of greed.

Mary Morstan hires Holmes to solve her father’s disappearance, leading Watson to admire her resilience. Their romance culminates in a proposal, humanizing Watson’s character and contrasting Holmes’ detached rationality. Their subplot adds emotional depth to the mystery.

Critics note the novel’s reliance on colonial stereotypes, particularly in its portrayal of Tonga, an Indigenous character depicted as a “savage.” Some argue the plot’s pacing lags compared to other Holmes stories, while Mary Morstan’s passive role reflects Victorian gender limitations.

This novel expands Holmes’ cocaine use and deductive flair while deepening Watson’s personal life—a contrast to A Study in Scarlet. Its focus on colonial consequences distinguishes it from Holmes’ typically London-centric cases, offering a darker critique of Victorian society.

The story’s exploration of greed, ethical compromise, and colonial legacy resonates in modern discussions about historical injustice. Holmes’ investigative techniques remain a blueprint for detective fiction, and the novel’s pacing and twists keep it engaging for contemporary readers.

Thaddeus Sholto—an eccentric art collector—bridges the mystery by revealing his father’s treason. His nervous demeanor and guilt-driven attempts to compensate Mary Morstan illustrate the generational impact of greed. His subplot underscores the novel’s theme of familial obligation.

Doyle builds suspense through cryptic clues (e.g., the “Sign of the Four” map), sudden deaths (Bartholomew Sholto’s murder), and timed chases. Holmes’ cocaine use and Watson’s romantic tension add layers of intrigue, keeping readers engaged until the treasure’s fate is revealed.