Silently following orders is a coward"s path. Those words belong to Junk Dog, an underground contender in Megalo Box—a modern form of boxing that employs mechanical appendages called Gear to boost speed and strength. Though the young fighter is brimming with talent, the illicit nature of his bouts forces him to earn a living by throwing matches at the behest of his handler, Gansaku Nanbu. The situation shifts when Megalo Box champion Yuuri slips into his dilapidated arena posing as an ordinary challenger. Knocked out in a single round, Junk Dog receives a new dare: "If you truly wish to face me again, climb your way up to my ring and earn a place there."
Fuelled by fierce anticipation and the backing of the syndicate that sponsors his throw‑matches, Junk Dog steps into Megalonia—a global tournament that will crown the supreme Megalo Boxer. Without a personal moniker, he adopts "Joe" and begins his ascent from the very bottom of the rankings. With a mere three months to secure qualification, Joe must confront opponents far beyond his previous experience in order to meet the challenge set by his rival.
