Vaudevillian Larry Haines (Bob Hope) sets out for California seeking fame and fortune, but instead he finds himself entangled in a world of intrigue and espionage. On the train ride to the coast, Haines meets Karen Bentley (Madeleine Carroll), a beautiful Brit with a big secret: She’s a spy who is carrying top-secret codes. When Nazi agents assume Haines and Bentley are colleagues, they frame Haines for murder, forcing the mismatched duo to go on the lam together.