The Sign of the Four

A secret pact. A mysterious treasure. A murder that baffles the police—and only Holmes can solve. In The Sign of the Four, Sherlock Holmes and Dr. Watson face a twisting tale of betrayal, hidden riches, and revenge that stretches from colonial India to the foggy streets of London. When Mary Morstan receives a cryptic invitation and a priceless pearl, she turns to Holmes for help. What follows is a deadly chase through riverside slums and locked rooms, unraveling a conspiracy that began decades ago. This thrilling novel introduces key elements of the Holmes universe—including Watson's romantic life—and remains one of the most beloved and suspenseful works in the canon.