During King Jungjong's reign, the Chosun capital is attacked by an unknown man-eating creature. It is up to a group, made up of an exiled soldier, his daughter, and a royal messenger, to fight off the monster and protect the king.
This event was during the time of King Jungjong of Joseon Dynasty. When he knew that there was a monstrous creature frightening the villagers near Mt. Inwangsan, he told a previous general to learn more about it and then they found out that the monster was real. The film presents a good balance of mystery, thriller, action, comedy, and romance.