On the turbulent border of Country K, where conflict rages year-round, police officer Song Shao loses his comrade during a mission. Because of the organization’s schemes, his wife is also implicated and killed. To protect his only daughter, Song Shao retires and lives in hiding under a false name, while secretly tracking the enemies who destroyed his family. At last, when his daughter is drawn into a kidnapping case, his foes reveal themselves, and a bloody battle begins