Emmy Ritter, once a popular German actress in her youth, returned to Germany to sell her old family home. She was arrested, sentenced to be executed and sent to a concentration camp. Her attending physician in the camp, Dr. Ditten, had been a fan of her and helped her sent a letter to her son Mark Preysing.
Mark rushed to Germany after receiving the letter and sought the assistance of police, locals, family friend Fritz Keller, and Countess Ruby von Treck; all refused to help and told him to go back to the United States immediately. Having inherited his mothers outspoken, free-spirited ways, a frustrated Mark soon aroused the attention of the Gestapo.
Mark ended up meeting Dr. Ditten through Ruby, who recognized Mark and sympathised with him. He poisoned Emmy, causing a death-like coma sleep, so that Mark would need to make arrangements to claim his mothers body and get her out of the camp. Fritz, not knowing that Emmy was alive, agreed to help.
Mark and Fritz got Emmy out but she was too weak and needed rest, so Mark brought her to Ruby, who turned her mansion into a girls finishing school after her husband died. Ruby took them in for the night, but refused to offer more help; as her survival depends on her relationship with General Kurt von Kolb, an older man insanely jealous of any man around Ruby.
But seeing the mother reunited with the son woke the American in Ruby, adding to the attraction already growing between Ruby and Mark; she finally decided to not only help Mark and Emmy, but leave with them.
Mark, Frtiz and Emmy headed for the airport first, Ruby was about to join them when General von Kolb returned, having sensed that Ruby was helping Mark. Torn between her patriotism towards both Germany and the United States, she decided to stay and hold off General von Kolb, so that Mark can get on the airplane safely.