Ambitious yakuza Kenji befriends harmonica-playing bartender Chuji, who moonlights as a part-time drug-dealer for the opposing gang. Their friendship is threatened by Kenji’s plans for advancement, as well as by his bodyguard’s growing jealousy of Chuji.

https://www.imdb.com/title/tt0303780/plotsummary?ref_=tt_ov_pl