Aldo Martini, a famous singer, meets Mara during a tour of Argentina and decides to marry her. When they return to Rome, Mara is kindly welcomed by Lia, Aldo's daugther from a previous marriage, while his son Gianni seems to be hostile. Mara behaves strangely, which makes Gianni believe that she is trying to hide something from her past. Mara has a secret. She is a widow, having lost her husband and daugther during the war. But one day, the husband reappears, claiming that his death was faked by an act of espionage. Mara is schocked. Her first husband agrees to leave and to reunite her with her daughter, on condition that she pays him a big amount of money. Following the advice of a friend, Mara accepts his conditions, but when she delivers the money, the man escapes without bringing her the child. Aldo, who was kept in the dark about the happenings, finds out that Mara met with another man and believes that she betrayed him. He hunts for her without giving her the chance to clear the misunderstanding. Mara seeks refuge at a friend's house. When the blackmailer calls her again, she decides to meet him at the train station, where she will give him a diamond necklace in exchange for her daugther. But when Mara turns up without the necklace, the man tries to kill her. Gianni, who in the meantime discovered the truth about the woman, can stop him. Aldo also joins in the fight. While the blackmailer tries to escape, he is knocked down by a train. Before he dies, he asks for forgiveness. Mara can finally embrace her daughter and live a happy life with her husband.