The Search
Trains bring homeless children (Displaced Persons or DPs), who are taken by Mrs. Murray (Aline MacMahon) and other United Nations Relief and Rehabilitation Administration (UNRRA) workers to a nearby transit camp, where they are fed and cared for. The next morning, the children are interviewed by UNRRA officials to try to identify them and reunite them if possible with their families.
A young boy named Karel (Ivan Jandl) responds "Ich weiß nicht" ("I don't know") to all questions. He grew up in a well-to-do Czech family. The Nazis had deported his sister and doctor father, while the boy and mother were sent to a concentration camp. They eventually became separated. After the war, Karel survived by scavenging for food with other homeless children.
The next day, the children are split up into groups and loaded into trucks and ambulances to be transferred to other camps. The children in Karel's group are at first terrified because the Nazis often used ambulances to gas victims, but are eventually coaxed into the vehicle. During the trip, the smell of exhaust fumes causes the children to panic. Karel's friend Raoul manages to open the back door, and the children scatter in all directions. Karel and Raoul try to swim across a river to escape from two UNRRA men. Raoul drowns, but Karel hides in the reeds.
Later, Karel encounters an American army engineer, Steve (Montgomery Clift), who takes care of him. He starts teaching the boy English. Because Karel cannot recall his name, Steve calls him Jim.
When Jim sees a boy with his mother, he starts to remember his own mother and the last time he saw her, near a fence in the concentration camp. He runs away one evening thinking the fence is nearby. Jim finds a fence at a factory, but cannot find his mother among the workers going home. Steve eventually finds Jim and tells him that his mother is dead (Steve has reason to believe she had been gassed) so he will stop searching for her. He also informs Jim that he is going to try to adopt him and take him to America to start a new life there.
As it turns out, Karel's mother, Mrs. Malik (Jarmila Novotná), is alive. In a parallel story, she has been searching for her son. By chance, she begins working for Mrs. Murray at the same UNRRA camp where her son had been processed. After a while though, she resigns to resume her nearly-hopeless search for Karel.
That same day, Steve takes the boy to the UNRRA camp before leaving for America. He hopes to send for the boy once the paperwork is completed. Mrs. Murray remembers the boy. Suspecting that Jim is Karel, she hurries to the train station to bring Mrs. Malik back, but the train has already left. Then, she sees Mrs. Malik on the train platform; she had changed her mind and decided to stay.
Mrs. Murray takes her back to the UNRRA camp and has her greet the newest group of children. Steve tells Jim to join the new arrivals. Mrs. Malik begins to organize the children and bids them to follow her. Jim walks past without recognizing her. Mrs. Malik almost makes the same mistake, but then turns and calls, "Karel!", and the boy and his mother are reunited.
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