Richard "The Imp" Audaine is a clever but dissolute orphan whose guardian and friends are trying to lead him from the path of ruin and back to his senses.

Adventerous engineer Robert Clay, goes to a South American country on an assignment by rich American Ted Langham to open an iron mine. While Robert is there, the unscrupulous General Mendoza tries to convince him to divide the mine's assets between them and President Alvarez. Mendoza starts a revolution against Alvarez when he and Clay will not go along with the plan, but he eventually is defeated after a long battle. Clay then is able to pursue his relationship with Hope, Langham's daughter, who has accompanied her father to South America.

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.