Casey Berman (Scott Adkins), who has unique skills and strong martial arts, is about to enter the marriage hall with his favorite woman Namiko (Mika Tsuboi), and usher in the crystallization of their love. One night, Casey went out shopping, but Namiko, who was alone at home, was brutally killed by an intruder. Unable to suppress the resentment and sadness in his heart, Casey indulged in the outburst of anger. After that, he washed away the past and came to the Koga Dojo in Thailand where his old friend Nakahara (Ken Kosugi) practiced with his luggage, but the pain of losing his wife made this Kongwu man unable to control his emotions, like a beast that could run away at any time. One day, a fellow Taoist in the dojo was killed, and the murderer's method of committing the crime was exactly the same as the murderer who killed Namiko. It was learned from Nakahara that all this might be caused by Goro (Shun Sugada), who had a lot of ties with the dojo back then and is now the leader of the Golden Triangle generation of gangsters. Carrying a deep hatred, Casey hits the road again...