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. Nobume also makes a stunning revelation regarding the Tendoushuu, a secret organization pulling the strings of numerous factions, and their leader Utsuro, the shadowy figure with an uncanny resemblance to Gintoki's former teacher. Hitching a ride on Sakamoto's space ship, the Yorozuya and Katsura set out for Rakuyou, Kagura's home planet, where the various factions have gathered and tensions are brewing. Long-held grudges, political infighting, and the Tendoushuu's sinister overarching plan finally culminate into a massive, decisive battle on Rakuyou.

Based on the story by manga master Leiji Matsumoto (The Cockpit, Queen Emeraldas), the 55 minute featurette picks up one year after the events of Galaxy Express 999 in which a young boy named Tetsuro and his motherly companion Maetel worked to rid the universe on the Mechanized Empire who had taken over Earth. (Source: AniDB)

A remake of episodes 12-13 of the TV version.

The alien Wulgaru's last assault against humanity was foiled by the heroic actions of the genetically enhanced humans known as the Evolved Children in their advanced AHSMB battle armor, but now a new attack has been launched against Earth under an even deadlier champion, Diorna, created from the fusion of DNA from two Wulgaru Royals. Unfortunately, Izuru Hitachi, the leader of Team Rabbits who defeated the Wulgaru Royal Jiart, is still out of action and recovering, so the task of marshalling the Majestic Princes and stopping Diorna falls upon the unready shoulders of Toshikazu Asagi. Together with the remaining members of Team Rabbits and the recently created Team Fawn, it’s up to Asagi to hold the line against the most ruthless adversary yet. (Source: Anilist)