Across the Divide (1921)

Left in the care of his half-breed brother, Buck, by his dying mother, Wallace Layson has no knowledge of his family history. His father, knowing that his son will inherit a ranch on his 21st birthday, tries to secure the property for himself by persuading a dance hall girl to come between the boy and his fiancée. When Buck learns of the plan he decides to foil it without his half-brother knowing.