The Sign of Four by Arthur Conan Doyle

A dense yellow miasma swirls in the streets of London as Sherlock Holmes and Dr Watson accompany a beautiful young woman to a sinister assignation. \n\nFor Mary Marston has received several large pearls ? one a year for the last six years ? and now a mystery letter telling her she is a wronged woman. If she would seek justice she is to meet her unknown benefactor, bringing with her two companions. \n\nBut unbeknownst to them all, others stalk London?s fog-enshrouded streets: a one-legged ruffian with revenge on his mind ? and his companion, who places no value on human life?