In 1939 London, Miss Guinevere Pettigrew is a middle-aged governess who finds herself once again unfairly dismissed from her job. Now she must seize the day if she wants a job. She does this by intercepting an employment assignment outside of her comfort level as social secretary. Arriving at a penthouse apartment for the interview, Miss Pettigrew is catapulted into the glamorous world and dizzying social whirl of an American actress and singer, Delysia...

A traveling entertainer gets more than she bargained for during a stopover in a South American port town. There she meets a handsome yet aloof daredevil pilot, who runs an airmail company, staring down death while servicing towns in treacherous mountain terrain. Both attracted to and repelled by his romantic sense of danger, she decides to stay on, despite his protestations.