In the alien-infested city of Edo, Gintoki and his Yorozuya comrades Shinpachi and Kagura struggle to make ends meet. Their routine changes when Katsura, Gintoki's old friend and rebel leader, vanishes after a vicious attack. While Shinpachi and Kagura hunt for clues about Katsura's disappearance and his attacker, Gintoki undertakes a separate task: retrieving the stolen Benizakura sword for a blacksmith. As these missions intertwine, the trio uncovers a dark conspiracy surrounding the dangerous sword. Determined to confront the enemy head-on, Gintoki, with the help of unexpected allies, embarks on a risky mission that challenges them like never before.