King Shadov (Charles Chaplin), the newly deposed monarch of a small European country, arrives in New York to face a life in exile. No sooner does he get here, however, than he discovers that his prime minister has stolen the entire royal treasury and departed for parts unknown. Stranded in New York in a luxury hotel without any money, the king tries to adjust to life in America and elicit interest in his plan for the peaceful use of nuclear power. He finds America in 1957 to be too noisy for his taste, however -- a run-in with some rock & roll dancers leads to some slapstick antics, and he doesn't take much to modern movies or the blaring entertainment that goes with them. He meets a pretty young lady (Dawn Addams) in a slightly risqué slapstick encounter in which he is trying to "rescue" her, and she maneuvers him into helping to plug a deodorant on television. The king proves so beguiling on the small screen that he is deluged by offers from advertising agencies, which he rejects at first. But the king soon finds that advertising may be the only thing he can do to earn enough money to keep him living like a king in exile, and he tries to work the system to his advantage, his earnings from television enabling him to remain in the country and push his peaceful nuclear plan. He soon finds the true dark side of life in the United States, however, when he crosses paths with an unhappy little boy (Michael Chaplin, the star/director's own son) whose parents are about to be jailed as part of the anti-Communist hysteria of the period. In the end, the king provides a shelter to the boy but compromises himself in the process, and while he does make the Congressional committee investigating him look foolish, he sees that he has done all of the good that he can do for now in the United States and leaves.