Sugimoto's obsession with gold stops mattering the moment you realize he's actually trying to save a kid who's already decided she doesn't need saving. Season 4 forces every character to reckon with what they've sacrificed for a treasure that was never the real prize. The comedy still lands, the survival details still grip you, but underneath it all is this quiet devastation: Asirpa has grown up, and Sugimoto is finally understanding what that costs.
Sugimoto the Immortal and Asirpa press deeper into their hunt for scattered Ainu gold, but the competition has grown fiercer and more desperate. Former convicts bearing tattooed maps of treasure locations close in from all sides, each willing to kill to keep their secrets buried. Asirpa has changed since her time away,more resolute, harder to predict, forcing Sugimoto to reconsider what their partnership really means. As their ragtag group pushes north, an unexpected ally attaches himself to the crew, complicating an already volatile dynamic. Hijikata's rebel faction scrambles to gather the tattooed skins through whatever brutal means necessary, only to stumble into a trap set by one of the most vicious prisoners still alive. Meanwhile, First Lieutenant Tsurumi orchestrates events from the shadows, playing factions against each other, though even his superior planning hits a wall: he needs Asirpa herself to claim the gold. The treasure hunt transforms into something darker and more personal, where loyalty splinters and survival becomes the only currency that matters. The endgame finally arrives.