Former doctor Jim Howard (Herbert Marshall) helps desperate Margot Weston (Barbara Stanwyck), pregnant and unmarried; when her son is born, Jim helps her place the baby with Phil Marshall (Ian Hunter) and his wife, on the condition that neither the Marshalls nor the child ever know Margot is his mother. Five years later, Margot is now a well-paid buyer for the store owned by Harriet Martin (Binnie Barnes); she meets Jim again, and a romance begins to blossom, but she's off to Paris on Harriet's behalf. There, Margot is wooed by the charming but carefree Count Giovanni Corini (Cesar Romero) and she happens to meet her son Roddy (Johnnie Russell), traveling with his aunt, as Mrs. Marshall has died. On the trip back to America, Margot and Roddy become very close, while Corini, on the same ship, continues to pursue Margot. At home, she becomes convinced that Jessica (Lynn Bari), Phil's new fiancee, doesn't love him, and will be a bad mother to Roddy, so she decides to break up the engagement, but Jim, beginning a career as a scientist, reminds her of her earlier promise not to interfere in the boy's life.