Born the illegitimate son of Hong Jeong Seung, Gil Dong rebels against the feudal social system and becomes a righteous outlaw. He organizes the Halbin Dang gang, confiscates the wealth of corrupt officials, punishes them, and rescues the poor. The royal court makes every effort to capture him, but to no avail. Finally, Gil Dong founds the kingdom of Yuldo and becomes its king.