Daijiro Akagi, who has lived his life on sheer guts alone, and his younger brother Kojiro, whose cunning far exceeds that of the average person, are a pair of small-time thugs battling it out in Osaka. One day, the two find themselves saddled with a debt of nearly 10 million yen at an illegal mahjong parlour run by the Jishin-gumi. If they cannot repay it within a week, their lives will be in danger...