You're watching the same arc you've seen before, except now the budget finally caught up with how ridiculous it actually is. The comedy timing gets sharper, the action sequences breathe with actual space and weight, and Gintoki's chaos reads different when the animation isn't holding it back. This is Gintama proving it doesn't need a new story to justify itself, it just needed the resources to let what already works absolutely detonate on screen.

Gintoki Sakata runs the Odd Jobs agency in an Edo that aliens have conquered and colonized, taking whatever work comes along with his employees Shinpachi and Kagura. When Katsura, leader of the Joui rebels and an old acquaintance of Gintoki, vanishes after a savage attack by an unknown assassin, Shinpachi and Kagura set out to find him and learn who struck him down. Gintoki, meanwhile, accepts a request from the blacksmith Tetsuya to recover a stolen blade called the Benizakura. As the two cases begin to overlap, secrets from Gintoki's samurai past surface, and the crew is drawn into a conspiracy built around the sinister sword. The result is a feature-length mix of action, comedy and science fiction.