After joining the resistance against the bakufu, Gintoki and the gang are in hiding, along with Katsura and his Joui rebels. The Yorozuya is soon approached by Nobume Imai and two members of the Kiheitai, who explain that the Harusame pirates have turned against 7th Division Captain Kamui and their former ally Takasugi. The Kiheitai present Gintoki with a job: find Takasugi, who has been missing since his ship was ambushed in a Harusame raid. Hitching a ride on Sakamoto's space ship, the Yorozuya and Katsura set out for Rakuyou, Kagura's home planet. Long-held grudges, political infighting, and the Tendoushuu's sinister overarching plan finally culminate into a massive, decisive battle on Rakuyou.