In the third year of the Zhonghe period at the end of the Tang Dynasty, outside Yunzhou City in the north, the Khitan cavalry looted the land, leaving thousands of miles of scorched earth and refugees everywhere. Gu Yingfei (16 years old) disguised himself as a refugee and secretly searched for the Khitan murderer who killed his family; Han Xingluo (17 years old) followed the old soldier Zhou Hu to work as an oddball at the border post and make a living by his strength. The two met due to a Khitan skirmisher's robbery and were forced to join forces to resist. They accidentally killed a Khitan primary school soldier and were chased by Khitan soldiers. At the same time, they were involved in the secret treasure competition between Xuan Jizi and Mo Ying. They learned about the grievances between the secret sects "Hanyue Pavilion" and "Shadow Hall", as well as a secret treasure "Mountain and River Map" that can affect the pattern of the northern territory (foreshadowing: the Mountain and River Map is not only a map, but also hides the military deployment of the vassal town and the Khitan weakness).
