"Samurai Jack" first aired on Cartoon Network on August 10, 2001. Season 4 of the popular series aired on September 25, 2004, but it did not have a proper conclusion to the story, and fans were left hanging.
On October 2015 the series got a green light to do season 5, and on March 1, 2017, the new season premiered on the Toonami programming block of Adult Swim. After almost three months from its return, "Samurai Jack" aired its last episode.
Many critics agree that "Samurai Jack" season 5 finale is bittersweet, and that it was an amazing episode.
Despite the major heartbreaking event, the series was given proper closure. Creator Genndy Tartakovsky promised that the last episode is going to be a tear-jerker, and he certainly kept his word.
The official synopsis of Season 5 says that it has been more that five decades since we saw Samurai Jack, and time has not been kind to our hero. Every time Portal has been destroyed by Aku, and because of time travel, Jack has stopped aging, he is cursed just to roam around endlessly forever.
Jack finally faced Aku
After spending several years of training, the most awaited moment has come. Jack went head-to-head with Aku to defeat the demon. Aku, on the other hand, was trying to figure out how to best bring Jack down.
He let the whole world know that he is going to kill our hero.
Many viewers let out a huge gasp when Aku ordered his daughter Ashi to battle with Jack instead of dealing with him himself. He controlled her as she battled it out with the warrior that she loved. However, when Jack professed his love for Ashi, she was able to break out of Aku's control.
The consequence of rewriting the world's timeline
Jack and Ashi used the powers that the latter inherited from Aku to time-travel to the past. To make Aku not exist in the future, Jack must rewrite the timeline of the world, however, to erase Aku from the future would also mean that Ashi never existed. She will be wiped out from the timeline, just like her demon father.
Back in the past, just as Ashi was walking down the aisle to marry Jack, the beloved heroine died. Jack was left reminiscing about his life and his journey under a cherry blossom tree.
A lot of viewers had tears in their eyes when the last scene of "Samurai Jack" season 5 finale was shown. The ending is heart-wrenching; however, many agree that it's the best possible way to end the story, no matter how heartbreaking it was. It may be sad that Ashi had to die, but Jack still has his family, and best of all, the world is now free of Aku.