In 1945, Mischa, a Red Army officer, discovers a frightened German girl, Anna, huddled in a Berlin cellar. He gives her a safe escort home and wins her gratitude. Seven years later, Mischa returns to Berlin as a civilian engineer in charge of factory production. He remembers Anna and searches for her in the western sector, where he is observed by the Secret Police. He is instructed to report to the police chief, Kazanow, who reprimands him for leaving the eastern zone. While there, Mischa discovers that Anna is Kazanow's secretary. Factory manager Schultz resents the Russians and attempts to murder Mischa, who is seriously injured but recovers and wins Schultz's respect and confidence. Schultz tells Mischa he is planning to escape to the western zone, and Mischa gives him the address of a contact in free Germany. Schultz's plan is uncovered by the police and he commits suicide. When they find the contact's address, Mischa and Anna, now deeply in love, are forced to flee. There, the Russian secret police trick Anna into a car and start the drive back to the eastern zone from which there is no way out.