A young girl rebelling against her strict school is tricked by a romantic suitor into prostitution.

On a whim and to save the good name of her sister, Dolly Erskine, a light-hearted young woman, declares that a riding master is her husband, not realizing that they have crossed the border into Scotland and that the confession of marriage is binding. However, she has unwittingly become the wife of an earl, falling in love with him in time to prevent a divorce decree. While Dolly is falling in love, the earl continues to pose as a riding master, and as such wins the heart of his pretty bride. Based on the play "Gretna Green," by Grace Livingston Purniss.