Megalo Box is a unique boxing style that employs a set of metallic frames referred to as Gear. "Gearless" Joe achieved legendary status in the sport after emerging triumphant in the maiden Megalonia tournament. However, Joe's fortunes took a downturn following his defeat to the second tournament champion in an exhibition match, leading to his disappearance for several years. Years later, the disillusioned Joe adopts the moniker "Nomad" and is content with a covert existence, engaging in off-the-grid fighting. He struggles with vivid hallucinations, regularly patching them up with painkillers. During one of his fights, Joe takes on Chief, who deliberately concedes defeat to some crooked gamblers for a considerable payout. Chief hails from Casa, an immigrant community occupying illegal terrain, and intends to earn enough money to legalize the community's land. Joe initially hesitates to join the cause, but he ultimately decides to assist Casa.