An Osaka gangster Shimamura just got married. His new bride, Mineko is also involved in drug trafficking. When she goes to China to make a deal, things get botched pretty badly. Shimamura must travel to save her and recoup his employers’ losses.
A woman diver in great peril is rescued by Shinji, a fisherman. But his deed is belittled by Takiko, another diver, as a rash act. Her attitude, however, is nothing but a cloak to hide her affection for him. Shinji, hard working and manly, becomes the focus of many yearning eyes and Seikichi, the boss' son, picks a quarrel with him and violent fight ensues in which Shinji kills a man in self-defense.
Two brothers, Takamaru and Kikumaru, are living with their father, Hakuraku-Ou, until one day Hakuraku-Ou is killed by "Death's-Head" Ginnosuke, a villain skilled in the art of sorcery. Hakuraku-Ou had long been seeking a Tiger Seal which, together with the Dragon Seal in his possession, would reveal the location of a huge ancestral fortune. But on the very night that the Tiger Seal was found, it was stolen by Tomomitsu, Ginnosuke's chief. When the two brothers receive the Dragon Seal from their father just before his death they determine to go to Death's-Head Castle, in order to recover the Tiger Seal.
