Jabez Wilson, a man with bright red hair, is asked to join a Red Headed League and accept a very strange job offer. James McCarthy is accused of murdering his father, but Alice Turner, the girl James loves, believes he is innocent. A man finds a hat and a dead goose in the street after witnessing a fight. He cuts the goose open, and finds a blue diamond inside it. These three strange stories arouse the curiosity of the brilliant detective Sherlock Holmes. What will he make of them all?