Hong Gildong (played by Lee Bong Won) and Ddong Gildong (played by Kim Jeong Sik), disciples of the Hong Gildong Master School, train under master assistants with distinct specializations. Meanwhile, an evil group called Baekgolgyo awakens the Heavenly Demon King and the Underground Demon King from their 800-year deep slumber to rule the world with evil. Upon learning this, the headmaster of the master school dispatches Hong Gildong and Ddong Gildong to the scene... Faced with the immense power of the two demon kings, what will become of Hong Gildong and Ddong Gildong...?