It's 1917 in the town of Wharton, Texax. On Valentine's Day, Young Elizabeth Vaughan (Hallie Foote) defies her wealthy parents by running off and marrying a young man of humble prospects.
Her parents have not spoken to her since her marriage even though the couple lives in a rooming house nereby; they are struggling financially and she is pregnant. This film to some extent autobiographical, is based on the story of Horton Foote's mother and father.
On Valentine's Day is about the unselfish love of a man and a woman, about abiding love within family, about the emptiness of living without love - all enduring themes of human existence.