After his father leaves when he is very young, Kyosuke Murata grows up under the thumb of his overprotective mother, Shizuko. When he reaches adulthood, he is thrown into the harsh, violent world of Japanese gangland when his mother becomes involved in a gang-related crime. He goes up against the Murata-gumi organization, only to find that his estranged father is its head. Rising up through the ranks, Kyosuke eventually unites half the gangs in Japan beneath his own leadership, only to find that the other half have also combined to resist his new power, starting the greatest gang war in Japanese history.

(Source: The Anime Encyclopedia)