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The Sign of the Four

Arthur Conan Doyle

The Sign of the Four

The Sign of the Four

Arthur Conan Doyle

Fiction, Mystery & Detective

In Arthur Conan Doyle's second full-length Sherlock Holmes novel, the iconic detective and his steadfast chronicler Dr. Watson are drawn into a labyrinthine mystery by Miss Mary Morstan. For years, she has received a single, anonymous pearl annually, following the inexplicable disappearance of her father a decade prior. Now, a cryptic letter summons her to a clandestine meeting, promising to shed light on her past. What begins with a missing father and a string of pearls quickly unravels into a complex tale involving a lost treasure from India, a pact among four convicts, and a trail of betrayal and murder that spans continents and generations, all leading to a thrilling chase along the Thames.

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The Sign of the Four, initially titled just The Sign of Four, is the second of Doyle’s novels to feature the analytical...

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The Sign of the Four
The Sign of the Four
Standard Ebooks · 175 pages
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The Sign of the Four
The Sign of the Four
Project Gutenberg · 173 pages
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About The Sign of the Four

Chapter Summaries

1
Holmes uses cocaine while Watson criticizes his habit. Holmes demonstrates his deductive abilities by analyzing Watson's watch, revealing details about Watson's deceased brother. Miss Mary Morstan arrives seeking help with a mysterious case.
2
Mary Morstan explains her father's disappearance ten years ago and the annual pearl gifts she's received. She shows Holmes a letter summoning her to a meeting, and Holmes agrees to accompany her with Watson.
3
Holmes discovers that Major Sholto died shortly before the pearl gifts began, suggesting a connection. The trio travels to meet Mary's mysterious correspondent, examining a strange Indian diagram along the way.

Key Themes

Justice vs. Revenge
The novel explores the difference between legal justice and personal vengeance, as Jonathan Small seeks revenge for past betrayals while Holmes pursues justice through proper channels.
Greed and Corruption
The Agra treasure corrupts all who touch it, from the original theft to Major Sholto's betrayal, showing how wealth can destroy moral character and relationships.
Loyalty and Betrayal
The story contrasts true loyalty (Watson to Holmes, Tonga to Small) with devastating betrayals (Major Sholto's abandonment of his partners), examining the bonds that unite and divide people.

Characters

Sherlock Holmes(protagonist)
The brilliant consulting detective who solves the mystery through deductive reasoning and observation. He struggles with cocaine addiction and craves mental stimulation.
Dr. John Watson(protagonist)
Holmes's loyal companion and chronicler, a former army surgeon with a war injury. He falls in love with Mary Morstan during the case.
Mary Morstan(major)
A governess seeking answers about her missing father and mysterious pearl gifts. She becomes Watson's love interest and shows remarkable composure under pressure.
Jonathan Small(antagonist)
A one-legged ex-convict seeking revenge and his share of the Agra treasure. He orchestrated the theft but abhors unnecessary violence.
Tonga(antagonist)
A small, fierce Andaman Islander who serves as Small's companion. He kills Bartholomew Sholto with a poisoned dart.
Thaddeus Sholto(major)
The nervous, hypochondriacal twin brother of Bartholomew. He contacts Mary Morstan to make amends for his father's wrongs.

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