Overweight Boston spinster Charlotte is a repressed, self-esteemless woman completely dominated by her wealthy mother, Mrs. Henry Vale. When her sister-in-law Lisa Vale brings her friend Dr. Jaquith, a renowned psychiatrist, to visit Charlotte, he invites her to spend some time in his sanitarium. Soon Charlotte transforms into a sophisticated, confident woman and takes a cruise to South America. She meets married architect Jerry Durrance and they have a love affair in Rio de Janeiro. Six months later she returns home and confronts her mother with her independence. One day they have an argument and her mother has a heart attack and dies. Charlotte inherits the Vale fortune but feels guilty for her mother’s death. She decides to return to Dr. Jaquith’s sanitarium, where she befriends Jerry’s 12-year-old daughter Tina, who has been rejected by her mother. Charlotte takes Tina home to Boston with her and one day Jerry brings Dr. Jaquith to visit them there.