Insaan is an action romantic drama that follows the story of a young man named Shankar (Vinod Khanna), who is often mistreated by his stepmother and stepbrother, but Shankar bears this treatment for the sake of keeping his family together. Later, Shankar starts earning with utmost honesty and hard work, and manages to earn enough for himself. However, tough times fall on his stepbrother and stepmother, who are in urgent need of money. They devise a plan to take away all the hard-earned money of Shankar for themselves. Will the two succeed in their evil plan or be stopped by Shankar?