Zhao Tieshan, a hunter in the mountains, gathered the refugees and built the last line of defense at the border with his flesh and blood. Shen Zhao, an orphan from the previous dynasty, secretly planned to subvert the country with the help of people's courage, but lost his original intention among the iron-blooded guards. Ma Dachui forges swords to protect the city, Liu Niang refines poison to relieve disaster, Tuoba wanders between fighting fiercely and thinking, and Chen Boyong carries a heavy burden like a mountain. When the barbarian cavalry tramples through the snowy fields, and when the court's secret orders point out that the brave people are traitors, should they protect their home or their lives?