Based on Sidney Howard's play, a dominating mother tries to break up one son's engagement and the other's marriage.
Recently wed David Phelps (Joel McCrea) and biologist Christina (Irene Dunne) leave Heidelberg when Dave gets a job in New York, where Christina can work at the Rockefeller Institute. At his mother's home they are met by his brother Robert (Eric Linden), who is planning to marry Hester (Frances Dee). Mrs. Phelps (Laura Hope Crews) greets Dave and worries about him. Hester and Christina believe in letting children be. Mrs. Phelps puts Dave and Christina in different rooms. Christina tells her they plan to live in New York. Mrs. Phelps considers herself only Dave's mother and asks her not to take him to New York. Christina wants Dave to be on his own feet. Mrs. Phelps protests she is not selfish. She asks for sympathy from Robert, asks about Hester, and questions their love. Robert agrees to break with Hester.
Christina and Dave announce a baby is coming. Robert and Hester argue about his mother, and Robert tells her he is not sure. Hester gives him his ring back and cries hysterically. Hester confronts Mrs. Phelps and calls a taxi; but the mother disconnects the phone. Christina comforts Hester and tells Dave they must get out of that house. Dave tells Robert to let go of his mother's apron strings. Robert defends his mother, and she complains Dave hurt her. She puts Dave to bed, asks about Christina, and wants the four of them to be happy. Mother wants Dave to be master in his house and always come to her for advice. Dave tells Christina not to take sides and that he can't leave his mother now. She asks him to face facts that his mother has never let Robert marry; she fears her hold on Dave. Dave doesn't see it and defends his mother. Christina discovers Hester is gone, and Dave has to rescue her from an icy water hole.
The doctor recommends Hester leave that house and tells Robert there is nothing wrong with his mother's heart she often complains of. Mrs. Phelps asks Dave to help her and Robert get settled abroad. Christina tells Dave she is going with Hester and asks him to come with her and stay away from his mother. Christina criticizes his mother with scientific detachment. Mrs. Phelps says her husband did not love her, and so she found it with her sons. Dave decides to go with Christina. Robert stays and comforts his mother.
This drama is painful to watch, but it carries a powerful message about an overbearing mother who cannot let go of her adult sons. The independent Christina is able to liberate her husband from his mother.