The story takes place in an alternate version of Japan's Edo period, where aliens from outer space, known as the Amanto, have invaded and taken over the country. The Tokugawa Shogunate, the ruling government, has formed an alliance with the Amanto, allowing them to coexist with humans. As a result, many samurai have become unemployed, and the main characters of the show are part of a group of freelancers who take on odd jobs to make ends meet.
Having all 367 episodes (+ movies) in one set is a godsend. You can finally watch the slow-burn masterpiece without hunting for streaming rights. The show improves massively after the first ~25 episodes (once the author finds his rhythm). The final arcs ( Silver Soul ) stick the landing emotionally—rare for long-running shonen. Gintama Complete Series
Watch every single episode of the Gintama complete series. There is no "skip" list. Every episode contains at least one gag that will destroy you. The story takes place in an alternate version
A crucial bridge. This two-episode OVA/special directly connects the ending of Episode 367 to the events of the final movie. It is required viewing before moving on. Having all 367 episodes (+ movies) in one set is a godsend