A scraggly mouse named Chuta stumbles into Tokyo Harbor bearing scars and desperation. He's fled Devil's Island, where an ermine tyrant named Norio has enslaved mice through cruelty and fear. When word reaches Gamba and his crew of adventurers, they can't ignore the call. These rodent heroes set out across dangerous waters toward the island prison, ready to challenge Norio's iron grip and free the oppressed. What begins as a rescue mission spirals into something larger. The crew discovers that Norio's control extends beyond the island's shores, threatening other creatures fighting for survival. As they gather unlikely allies and navigate treacherous landscapes, the mice learn that liberation demands more than courage. It requires sacrifice, strategy, and the willingness to stand against overwhelming odds. This adventure captures the spirit of classic fantasy quests: ragtag heroes, impossible odds, and the question of whether ordinary creatures can topple extraordinary evil. The film balances genuine danger with moments of camaraderie and humor, creating a story that resonates with anyone drawn to tales of resistance and redemption.