Shelah Fane, a motion picture star filming in Honolulu, consults the mystic Tarneverro, her spiritual adviser, to decide if she should marry Alan Jaynes, a wealthy globetrotter she met on the boat to Hawaii. During a crystal ball session, Shelah confesses that three years earlier she fell in love with her co-star, Denny Mayo, and that she was in his house the night he was murdered. Agitated after the consultation, Shelah tells Julie O’Neill, her protegée, that she cannot marry Alan. Anna, Shelah’s maid, is greatly upset when, as she brings Shelah some orchids from stage actor Robert Fyfe, who is appearing in town, she sees Shelah tearing a photograph of Denny Mayo. That evening, just before a dinner party Shelah is giving, Julie and Jimmy Bradshaw, a tourist bureau employee who wants to marry Julie, find Shelah stabbed to death in her pavillion. Julie removes Shelah’s emerald ring. During his investigation, Inspector Charlie Chan of the Honolulu police finds the orchids crushed next to Shelah’s body with their pin missing. He also notices in the sand outside the pavillion a footprint made by a shoe with a hole in it. Chan gathers the guests, who were all in Hollywood at the time of Mayo’s murder, and relates an old saying: “Death is a black camel that kneels unbidden at every gate.” After Chan’s blundering assistant Kashimo finds the ripped photograph of Mayo, both Tarneverro and Julie secrete pieces of it. When Kashimo brings in a beach bum, who calls himself Smith and whose shoes match the footprints found outside the pavillion, Fyfe, Shelah’s ex-husband, confesses that he killed her. Alan, greatly upset, wants to leave immediately to catch a boat to the mainland, but Chan deduces that Fyfe could not have been at the pavillion when the murder took place, and warns the guests not to leave the island. Needing money, Smith, an artist, threatens Fyfe that he will tell what he overheard Shelah say in the pavillion unless Fyfe buys one of his paintings. After Fyfe gives him $100 and promises to pay $200 more, an unseen assailant shoots Smith on the beach. At Jimmy’s urging, Julie confesses to Chan that she took the emerald ring because it contains an inscription from Mayo; Shelah, she says, wanted to keep their relationship a secret. Chan learns from an Australian couple that Tarneverro is really Denny Mayo’s brother Arthur. Before Smith dies from his gunshot wound, he reveals to Chan that he heard Shelah tell Fyfe that she confessed killing Mayo to Tarneverro. Fyfe confirms this and says that after Shelah had found out that Mayo had a wife in England, she shot him during a quarrel. Fyfe says he confessed to her murder because he loved her and wanted to protect her memory. Smith also reveals that he took a diamond pin from the pavillion, which Chan notices, has a part missing. As Chan finds a scratch mark on the floor under the dinner table in Shelah’s house that he believes was made by the shoe in which the missing piece of the pin is probably still lodged, a knife is thrown at him. Chan deduces that Shelah’s murderer must have sat in the chair nearest the scratch. Meanwhile, Julie accepts Jimmy’s proposal and agrees to remain with him in Hawaii. Chan has the suspects sit where they sat the previous night. Tarneverro sits in the chair next to the scratch, but Chan, investigating further, learns that later the previous night, the maid Anna sat in the same chair. When Chan finds the piece of the diamond pin in the heel of her shoe, she reveals that she is really Mrs. Denny Mayo and admits killing Shelah. Tarneverro confesses that he came to Hollywood to find his brother’s murderer, and says that when Shelah confessed to him, he told Anna. He asks to share Anna’s fate. As Chan goes to arrest Anna, Jessop, the butler, who loves her, pulls a gun, but after a struggle, Chan disarms him. Jessop admits he shot Smith because he knew too much and that he threw the knife at Chan. Just then, Kashimo enters with a clue, but Chan instructs him to save it for the next case. More on Wikipedia
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