Young Stella Martin, the daughter of a Millwood factory worker, is secretly attracted to Stephen Dallas, a minor executive at the factory whose family was once wealthy. Stephen has broken his engagement to Helen, his long-time sweetheart, because he fears that his present lack of money and social position would not be good for her. Stella schemes to have a chance encounter with Stephen, and when the opportunity presents itself one afternoon when her brother Charlie goes to work at the factory without his lunch, Stephen is attracted to her. Soon they begin to see each other in the evenings, and Stephen asks her to marry him, even though she warns him that the differences in their backgrounds might be a problem. After their baby daughter Laurel is born, Stella becomes bored with her life as the wife of a staid, rising businessman and begins to exhibit social characteristics which Stephen finds unsuitable. After Stella insists on dancing with the kind, but loutish Ed Munn at the exclusive River Club, Stephen tells Stella that he will have to be spending more time on business in New York. Stephen's visits home become less and less frequent, and they eventually separate. Though Stephen does not think that Stella can provide the right atmosphere for Laurel, he allows Stella to keep the girl, knowing how much she loves her. Many years later, while Stephen is selecting a gift for Laurel in a New York department store, he encounters his former fiancée. Now Mrs. Morrison, a widow with three sons, Helen is delighted to see Stephen again, and the two rekindle their former love. Soon, when Laurel comes to visit her father, she stays with the Morrisons whose opulent life and family atmosphere are far different than her lower class life with her mother. Stephen wants to marry Helen and informs Stella through his lawyer, but she refuses to give him a divorce and asks for more money. She fears that Stephen and Helen are trying to take Laurel away from her and wants the extra money to give Laurel all of the things that she has with the Morrisons. At a posh resort to which she takes Laurel, a minor illness keeps Stella bedridden while the sweet and beautiful Laurel enjoys the company of rich young people. Laurel is grateful to her mother for the trip to the resort, but when Stella unexpectedly gets out of bed and dresses in her gaudy new clothes, Laurel is too embarrassed to let her new friends know that the woman they find so ridiculous is her mother. On the train home, Laurel and Stella each overhear some girls talking about their discovery that the gaudy woman at the resort is really Laurel's mother. Stella pretends to be asleep when Laurel looks in on her, but decides that she must give Laurel to Stephen and Helen if she is to have the kind of life she deserves. Though Stella makes Laurel think that she wants the divorce to go to South America with Ed Munn, Helen has been secretly visited by Stella and knows the painful sacrifice that Stella has made for her daughter. Some years later, the news of Laurel's forthcoming marriage to the wealthy Richard Grosvenor, III, reaches the newspapers, revealing that the wedding will be at the Dallas home in New York. As preparations are being made, Helen insists that the curtains in the living room remain open. Laurel cannot believe that her mother has not contacted her, but Helen tells her that Stella would never miss attending her daughter's wedding if she could. As the ceremony takes place, Stella is in the front of the crowd looking in the window. A policeman tells the crowd to move along, but Stella stays until after Dick kisses Laurel. Now confident of her daughter's happiness, Stella smiles and walks away.