In 2084, in the cutting-edge city of Yul City. Hong Gil Dong lives with his loyal companion Cheori on an abandoned airship, after being hated and banished by his brother Il Dong in childhood. One day, he rescues Ha Ryung, a beautiful warrior, who is attacked and in danger in the forest, and learns about the ruthless atrocities Hong Il Dong is committing against the people of Yul City. To save Yul City, which is in danger due to Hong Il Dong and his monster army, Gil Dong secretly returns to the city with his best friend Cheori and three bandits… Will Gil Dong be able to defeat the fearsome monster army and Hong Il Dong to save Yul City?