In the late 14th century, Joseon was founded, but the activities of "Dansim," a resistance group from the fallen Goryeo Dynasty, only grew stronger. In the midst of this, the Minister of Justice is assassinated by Dansim, and Park Je-myeong, the Vice Minister of War, is held accountable for this. Park Je-myeong, in danger, finds Hwang In-seo, the second-highest ranking official in Dansim, requesting naturalization, and begins a security mission with his son Do-wook, a junior official in the Ministry of War, which will determine the rise and fall of the government. However, the mission is failed by Lee Mu-yeong, and Park Je-myeong commits suicide as a result. Do-wook's persistent pursuit leads to a fateful meeting between Mu-yeong and Do-wook, and their confrontation leads to catastrophe.