Return Of The Jedi Explained

Luke Skywalker goes on his own journey in Return of the Jedi, with a dual mission to fight for the Rebel cause and to redeem his father. Darth Vader had once been an honorable Jedi, but fell under the influence of Emperor Palpatine. As the final battle draws near, Luke breaks off from Han and Leia's ground mission on Endor to confront Darth Vader and bring him back to the light. 

In a dramatic confrontation on the Death Star, Luke prevails over his father in combat. When the Emperor encourages Luke to strike Vader down and take his place, Luke resists — only to be struck with the Emperor's Force lightning. As the Emperor tortures Luke, Vader finally has a change of heart, and Anakin's goodness reawakens. He retaliates against the Emperor, throwing him to his death. Unfortunately, Vader does not survive the effort, and dies before Luke can get him off the space station. His final request is for Luke to remove the breathing mask that has so long been a symbol of terror in the galaxy, so that the man who was once Anakin Skywalker can look upon his son with his own eyes.

Even if the destruction of the second Death Star is arguably more important on a galactic scale, Luke's character arc is the most vital to the conclusion of Return of the Jedi. As Lucas' prequel trilogy would later underline, Luke's persistence in bringing his father back to the side of good finally resolves the central character arc in Star Wars: the story of Anakin Skywalker, whose sacrifice completes a story six movies in the making.