The New York police have decided to throw a testimonial in Charlie Chan's (Warner Oland) honor, but the Honolulu detective just can't seem to go anywhere without murder following him. It seems that a Manhattan nightclub singer has been murdered, and it is soon discovered that the victim had the name of every criminal in New York in her diary. Faced with such a long list of suspects, Chan is up against one of his toughest assignments ever. He enlists a jaded newspaper reporter (Donald Woods) and an attractive photographer (Joan Marsh) to help him track down the murderer, but the trio keeps running into dead ends and bad leads. They eventually crack the case, discovering that the killer was about the last person they expected.