Colonel Thorndyke brought home from India a diamond bracelet stolen from a Hindu idol by a British soldier. Theft from a Hindu temple was considered a crime in India, obligating one or more persons to hunt down the thief and bring back what was stolen. The members of the Thorndyke family soon learned that they were being watched but could not determine whether by English highwaymen or Indian pursuers. A mysterious death followed, and this determined Mark Thorndyke, the hero of the tale, to become a detective in the London police force for the purpose of unraveling the mystery.