Moralistic Aunt Elvira, has raised Elena Evans and believes that because of Elena's mother, Elena possesses "the scarlet strain." Aunt Elvira scolds Elena when the youngster is caught flirting with Van Presby. Elena and Van sneak out to a movie and then return home where Aunt Elvira demands that they get married. Van's uncle, Harvey Presby, prevents the hurried marriage and takes Elena to the home of Van's mother Edith Presby. Mrs. Presby accepts Elena and sends Van off to college. When Mrs. Presby discovers that Uncle Harvey, in whom she is interested herself, has developed an interest in Elena, she plans to marry Elena off to Joseph Fleming. Elena later rebels and refuses to marry Joseph. Van returns from college, and in a drunken state tries to take advantage of Elena. Uncle Harvey rescues her and marries Elena himself. "The scarlet strain" turns out to be the sin of a second marriage.