In the American Old West, a legendary race is on the horizon, drawing thousands to San Diego for a chance at a fifty million dollar prize. Amidst the fading era of horseback travel, contestants are free to choose any mode of transportation for this grueling six thousand kilometer journey. Enduring harsh terrains and covering vast distances daily, the Steel Ball Run proves to be a unique and challenging spectacle. Johnny Joestar, a young man once renowned for his horse riding skills but now disabled, visits San Diego to witness the race's commencement. There, he crosses paths with Gyro Zeppeli, a racer wielding two steel balls with extraordinary abilities. Witnessing Gyro's remarkable power firsthand, Johnny experiences a life-changing moment when he inadvertently taps into the steel ball's energy, enabling him to walk after two years of immobility. Driven by a newfound purpose and a desire to unravel the mystery behind the steel balls, Johnny embarks on a peculiar journey across America as a participant in the extraordinary Steel Ball Run.