Sonny Chiba stars as a fictionalized version of Masutatsu Oyama, the Korean-Japanese founder of Kyokushin karate, who trains in brutal isolation and takes on bulls bare-handed to prove the superiority of real fighting karate over commercialized "dance" karate. Adapted from the manga Karate Baka Ichidai, this was the first entry in a trilogy built around Chiba's portrayal of Oyama.