Based on the play by Armand and Gow, an American family takes in a nephew from the Hitler Youth who misbehaves.
Mike Frame (Fredric March) and Jessie (Agnes Moorehead) discuss the death of their sister and German brother-in-law in a concentration camp and the coming of their nephew. Leona Richards (Betty Field) agrees to marry Mike. Emile Bruckner (Skip Homeier) arrives and bows. Mike tells him that Leona is Jewish. Young Pat Frame (Joan Carroll) tells Emile that her father works on military secrets. Emile puts on his Hitler Youth uniform and talks to the maid Frieda (Edit Angold) in German. She refuses to help Germany and tells Mike that Emile thinks he is a spy. Emile says his father was a traitor to Germany and committed suicide. Mike and Leona try to reason with him. Mike tells him to change his clothes before lunch. Pat takes Emile to school. Emile calls girls stupid and teaches boys camouflage. Leona tells Emile that in America everyone is equal.
Emile learns that Jessie is moving out and tries to plot with her against Leona. Emile sees Stan Dumbrowski hanging up laundry and pulls it down, threatening Millie. At school Leona asks Stan why he is late. Millie is scared and lies for Emile. Leona makes Emile apologize before the class, but he calls America a cesspool and runs out. Mike finds him mowing the lawn, and he asks for money so that he can pay for the painting of his father he slashed. Mike tells him the truth about his father and gives him a book about him. Emile calls Leona names, and she slaps him. She tells Mike that Emile needs a licking, and they quarrel. Jessie comes in and asks if Mike wants her to stay. Emile says Leona slapped him and says he is glad Jessie is staying. Leona plans to move to Chicago.
Pat sees Emile take Mike's keys. She will tell her father, but Emile puts the keys back. Emile says he will kill her and hits her with a rod. Frieda finds Pat, and Mike carries her upstairs. Emile runs away. Boys look for Emile. Stan fights Emile, who has a knife, but eventually knocks him out. Jessie condemns Emile and all Germans, confessing he tried to use her against Leona. The boys bring Emile back. When Emile threatens to kill Pat, Mike grabs him; but Leona stops Mike from strangling him. Leona tells Emile how Pat planned his birthday party and bought him a watch. Mike has Frieda help Emile pack and calls the police. Leona suggests they let Emile stay. Pat comes in and lets Emile keep the watch. Mike asks Emile to tell what he learned about his father. He realizes his father must have been brave and says they beat him and kept him in the dark. Mike says they can be tough on him too and says they are keeping him.
This domestic drama shows the contrast between an extremely
fascist upbringing and American tolerance, revealing how dangerous
fascist tendencies can be but also how the way to cure them is
understanding instead of harsh punishment.