The story involves European importing firms in San Francisco, hurting from Chinese competition, who think their problem can be solved by keeping Occidentals out of Chinatown. They direct their business leader, an Eurasian woman named Sonya Rokoff (Luana Walters) to do this, and she hires another Eurasian, Victor Poten (Bela Lugosi), a scientist who needs money to continue his undisclosed experiments. Poten employs some thugs in Chinese disguise to create mayhem, enough that the police will close Chinatown. But newspaper reporter Joan Whiting (Joan Barclay) enlists aid of her friend, Martin Andrews (Herman Brix), a writer of a book about Chinatown, and they are immediately drawn into the action when Andrews' servant and information source, Willy Fu (Maurice Liu) is abducted by the thugs. As might be expected, Victor Poten has his own agenda, involving a superior race of his own creation, and he soon takes over and expands the project, to the horror of Sonya Rokoff. It may not make a lot of sense, but it keeps the plot boiling for fifteen chapters.