Nick Condon (James Cagney) is a journalist for the Tokyo Chronicler. He prints a story disclosing Japan's plan to conquer the world. The newspaper is seized by Japanese officers. Condon get the Tanaka Plan, a paper in which all the plans are laid in written. The Japanese spies who follow him think that Ollie and Edith Miller (Wallace Ford and Rosemary DeCamp) are the ones who discovered all the plan because they suddenly have a lot of money and are coming back to the USA. When Condon goes to the ship to say them farewell, he finds Edith dead. He can only see a woman's hand with a ring with a huge rubi. Back home, he finds Ollie, in a terrible condition. He gets from Ollie the Tanaka plan. Premier Giichi Tanaka (John Emery) wants his plans to remain secret, and sends Col. Hideki Tojo (Robert Armstrong) Capt. Oshima (John Halloran) and Hijikata (Leonard Strong) to follow him everywhere. Condon loses the document with the Tanaka plan. Ollie's disappeared, and the police arrest them in terms of scandal and much noise while having a party with two girls in his apartment, which is a complete lie. Condon meets Iris Hilliard (Sylvia Sidney), half American and half Chinese. At first, he suspects her of being the lady in the ship, then he doesn't. They fall in love. She seems to be betraying him, specially when Condon sees the ring with the ruby in her hand.