Park Heon-myeong, Munsu's father and the magistrate of Namhae, is murdered by Jang Hak-do, a local official who coveted his position and power. Young Munsu, fleeing to escape Jang Hak-do, lives in the mountains like a wild animal. Later, with the help of the venerable master Hak-jo, a friend of his father, and a young girl named Sook-i, he studies martial arts and scholarship, revealing his intelligence. As Munsu perfects his studies and martial arts day by day, a major event occurs. Mori, a Japanese pirate manipulated by Jang Hak-do, attacks master Hak-jo and pushes him off a cliff into the water. Munsu, unaware of this, mourns the death of master Hak-jo. After studying diligently, Munsu passes the imperial examination with honors and becomes a secret inspector. He returns to Namhae to thwart Jang Hak-do's plans. However, he falls into a trap set by Jang Hak-do and finds himself in grave danger. He is rescued by master Hak-jo, whom he believed to be dead. But when Munsu is attacked again by Mori, master Hak-jo sacrifices himself so that Munsu can defeat Jang Hak-do and his gang, but master Hak-jo ultimately dies.