In 1940, German-born engineer Kurt Muller (Paul Lukas), his American wife Sara (Bette Davis), and their children Joshua (Donald Buka), Babette (Janis Wilson), and Bodo (Eric Roberts) cross the Mexican border into the United States to visit Sara's brother David Farrelly (Donald Woods) and their mother Fanny (Lucile Watson) in Washington, D.C. For the past seventeen years, the Muller family has lived in Europe, where Kurt responded to the rise of Nazism by engaging in anti-Fascist activities. Sara tells her family they are seeking peaceful sanctuary on American soil; but their quest is threatened by the presence of houseguest Teck de Brancovis (George Coulouris), an opportunistic Romanian Count who has been conspiring with the Germans in the nation's capital.
Teck searches the Mullers' room and discovers a gun and money intended to finance underground operations in Germany in a locked briefcase. Shortly after, the Mullers learn resistance worker Max Freidank has been arrested; and, because he once rescued Kurt from the Gestapo, Kurt plans to return to Germany to assist Max and those arrested with him. Aware Kurt will be in great danger if the Nazis discover he is returning to Germany, Teck demands $10,000 to keep silent; and Kurt kills him. Realizing the dangers Kurt faces, Fanny and David agree to help him escape.
Time passes, and when the Mullers fail to hear from Kurt, Joshua announces he plans to search for his father as soon as he turns eighteen. Although distraught by the possibility of losing her son as well as her husband, Sara resolves to be brave when the time comes for Joshua to leave.
What does Joshua plan to do when he turns eighteen?
search for his father