In a secluded place in Japan, orphan Takashi (Mike Moh) and American youth Ken (Simeon Tsolov), who is like a brother, practice arduous training day after day under the guidance of their master Goken (Akira Oieyama). When the two finally feel the flow of qi in their bodies, the master promises to take them to a higher level of training, which will touch the destructive assassination fist. In their youth, Goken and his younger brother Gouki practiced with their master Hongtetsu (Togo Ikawa). Gouki, who was determined to become powerful, secretly read the master's secret book and learned the terrible assassination fist, but he could not control the fluctuations of murderous intent, and was eventually expelled from the master by Hongtetsu. As if it were another cycle, Ken seemed to be following Gouki's old path, and Goken was almost doing his best to avoid the tragedy from happening again. Until one day, Gouki came to the door, and the brothers had to face the fateful duel...