In 1923, the Korean teenager Kim Shun-Pei moves from Cheju Island, in South Korea, to Osaka, in Japan. Along the years, he becomes a cruel, greedy and violent man and builds a factory of kamaboko, processed seafood products, in his poor Korean-Japanese community exploiting his employees. He makes fortune, abuses and destroys the lives of his wife and family, having many mistresses and children and showing no respect to anybody. Later he closes the factory, lending the money with high interests and becoming a loan shark. His hatred behavior remains until his last breath, alone in North Korea.
Jûzô Murasaki is a boy miscast in his classroom, being frequently abused, tortured, beaten and humiliated by the bully Tôru Akai and his gang of juvenile punks. After years of repression, rejection and fear without facing Akai, he develops a psychopathic dual personality with a violent alter-ego. While living in the apartment 13 of a tenement building, he becomes unable to control his violent dark personality, who plots an evil revenge against his upper floor neighbor Akai and his family.