A boxing anime that stops mid-tournament to say: what if the real threat wasn't competition, it was assassination disguised as sport. The Shadow Clan doesn't box to win; they box to erase you. That single premise fractures everything Ryuuji thought he understood about his team's dominance, because you can't punch your way out of an opponent designed to kill you before the ref even calls the match.

Fresh from beating Black Shaft's makeshift Team America, the Golden Japan Jr. team goes back to training for the World Tournament, which is set to take place in Tokyo. Their preparations are interrupted by the Shadow Clan, a group that practices boxing as a method of assassination. The clan kidnaps Kiku to draw Ryuuji and the others into a showdown, one meant to settle which side is the real standard bearer for Japan's junior boxers. The result is a six-episode action and sports story built around high-stakes bouts in the ring.