Professor Nichols, an American educator, recalls the halcyon days of 1933 Germany before the rise of Nazism: As a teacher at the American Colony School, "Nicky" encourages Anna Muller and his other students to question Germany's lust for land. Meanwhile, at the German school across the way, the stern Dr. Schmidt exhorts Karl Bruner and the other boys to consecrate their lives to Adolf Hitler. Karl, who is attracted to Anna, comes to the American school one day and strikes up a conversation with her. After he tells Anna that he is a German who was born in America, Anna responds that she is American born in Germany and is now living with her grandparents there. To nuture their friendship, Nicky invites Karl to join him and Anna on a picnic, and soon Karl is a regular participant in their weekly outings. While running through the woods one day, Anna sees a little boy bound and gagged, but when she tries to free him, Karl tells her that the boy is being tested for his fitness to join a Hitler Youth group. Nicky states that that was Karl's last picnic, for he became enveloped in the Nazi storm that was sweeping Germany. By 1939, the New Order is underway, and Anna is now Nicky's assistant. As the students at the American school gather to celebrate Memorial Day, the Gestapo arrives and demands custody of all Germans, Poles and Jews at the school. When Anna's name is called, Nicky objects and is taken to headquarters to speak to the lieutenant in charge. At headquarters, Nicky meets Lt. Karl Bruner, who asserts that as a German citizen, Anna is subject to German law. When Nicky's entreaties to the American Embassy prove fruitless, he turns to his friend, journalist Franz Erhardt, for help. Franz, who is intimidated by his own little Nazi sons, is afraid to help Nicky, although he does suggest that Anna is probably being held at a labor camp. Nicky then goes to the Ministry of Education to petition a visit to the camp. There, he sees Karl, who orders him to give up his search for Anna. When Nicky agrees to do so if Anna is happy at the camp, Karl informs him that Anna is an instructor at the camp and takes him to see her. After Anna learns of Nicky's plans to free her, she insists that she wants to stay at the camp out of fear for his safety. Karl, who believes that Anna is becoming a "true German," tells her that he has recommended that she be allowed to study at the University of Berlin. Anna rejects his offer, however, and denounces his world as evil and rotten. When Anna formally declines the offer and disparages the "diseased New Order," Colonel Henkel, Karl's superior officer, sentences her to toil for one year at a labor camp. Henkel orders that Anna be kept under surveillance, and when Karl withholds reports of her defiant behavior, Henkel begins to doubt his loyalty. To test Karl, Henkel invites him and Nicky on a tour of the Ministry. Taking them to a clinic where women deemed unfit to have children are sterilized, Henkel announces that Anna's name has been placed on the patient list. After leaving the clinic, Karl finds Anna at the camp, and after warning her of the danger, declares his love for her. When Anna confesses that she also loves him, he suggests placating the state by having a baby, but Anna refuses, saying that the child would not be hers, but Hitler's. That night, Anna runs away and seeks refuge in a church. Soon after, the Gestapo arrives and orders the bishop to dismiss his parishioners so that they can find Anna. When, at the risk of his own life, the bishop defies their orders, Anna steps forward and surrrenders. Ordering Anna publicly flogged and then sterilized, Henkel sends Karl to the flogging as his representative. Unable to bear Anna's pain, Karl seizes the whip from her tormentor's hands and, after proclaiming his love for her, admits that he was wrong. Later, Franz informs Nicky that Anna has been sentenced to death, but Karl has recanted and will denounce his sins against the state in a nationwide broadcast of their trial. As Nicky and Franz are about to tune in the broadcast, the Gestapo arrives and orders Nicky to leave for Paris on the next plane. At the airport, as Franz walks Nicky to his plane, the trial begins and is broadcast over loudspeakers on the airstrip. In his opening statement, Karl quotes a poem by Goethe about freedom and, after observing that the German people have relinquished their freedom, proclaims "long live the enemies of Nazi Germany." Henkel reacts by ordering Karl and Anna executed in the courtroom, and the sounds of gunshots are heard over the speakers. Nicky then boards his plane and addresses the audience, telling them that "they must ask themselves tonight, before they go home, can we stop Hitler's children before it is too late?"