Dishonest mine owner Nicholas Rood finds a Black Doll on his desk and knows that vengeance is about to overtake him for murdering his former partner. He is knifed as he talks to his daughter Marian. She summons her fiancé Nick Halstead, a private detective. He finds that six people had a motive for the murder: Roods sister Mrs. Laura Leland; her son Rex; Roods associates Mallison and Walling; Esteban, a servant; and Dr. Giddings. Sheriff Renick and his deputy Red get the clues all mixed up, but Nick finally narrows the search down to one suspect.