A cikin Old West na Amurka, babbar gasar duniya tana gab da farawa. Dubun dubata sun yi layi a San Diego don yin tafiyar sama da kilomita dubu shida don samun damar cin babbar kyautar dala miliyan hamsin. Tare da zamanin doki ya kai karshen sa, ana baiwa masu hamayya damar amfani da kowace irin motar da suke so. Masu fafatawa za su jimre da yanayi mai wahala, suna tafiya har zuwa kilomita ɗari a rana ta cikin wuraren da ba a san su ba. Runfunan Kwallan Karfe shine ainihin abin da ya faru.
Saurayin Johnny Joestar, gurgu tsohon mai tseren dawakai, ya zo San Diego don kallon fara gasar. A can ya haɗu da Gyro Zeppeli, mai tsere da ƙwallan ƙarfe biyu a kugu maimakon bindiga. Johnny ya shaida Gyro yana amfani da ɗayan ƙwallan ƙarfen nasa don buɗe ikon ban mamaki, yana tilasta mutum ya harba bindiga a kansa a lokacin duel. A tsakiyar aikin, Johnny ya taɓa taɓa ƙwallon ƙarfe kuma ya ji ƙarfi yana ta ƙaruwa a ƙafafunsa, yana ba shi damar tsayawa a karon farko a cikin shekaru biyu. Yayi alwashin gano sirrin kwallayen karfe, Johnny ya yanke shawarar fafatawa a tseren, don haka ya fara abin birgewarsa a duk fadin Amurka akan Gasar Karfe Ball.
