When the leader of a vicious yakuza motorcycle gang gives up his violent ways to start a family, an act of brutal treachery transforms him into a force of pure vengeance. Armed with swords and baseball bats, the "Buyusenki" gang takes what they please as they terrorize the Kanto region. But their leader, Kyosuke Jinnai, has grown tired of the violence. In a bid to start a new life with his pregnant girlfriend, Kyosuke turns his back on the gang - a decision that will come back to haunt him when his former brothers take it all away in the blink of an eye. Devastated, Kyosuke vows to dish out the kind of justice that the courts can't stomach, and swim in the blood of pack he once ran with.