Gintoki and Nizo battle to the death on the deck of Takasugi's ship. The anti-battleship weapon Benizakura has infiltrated Nizo's mind, driving Nizo out of control. Gintoki fights back with a sword forged by Tetsuko. Nizo attacks with overwhelming strength, but slowly, the battle begins to turn in Gintoki's favor. Meanwhile, within the ship, Takasugi plans to use the Benizakura to overthrow the shogunate, but he is confronted by Tetsuya, the man who forged the Benizakura, Tetsuya's younger sister Tetsuko, and Katsura.