The sequel trilogy was a rumored film trilogy sequel to the original Star Wars trilogy, originally to be made by George Lucas/Lucasfilm Ltd., and set in the Star Wars Galaxy.

The sequel trilogy was to feature Luke Skywalker as a Jedi Master in his sixties, passing on the torch to the next generation of Jedi & the rebuilding of the Galactic Republic. It would also have concerned the reestablishment of the Jedi Order, as foreshadowed by Yoda's line in Return of the Jedi, "Pass on what you have learned." According to a 1983 Time magazine article, its main theme would have been "the necessity for moral choices and the wisdom needed to distinguish right from wrong". Based on statements at the time from Lucas, a major villain in the sequel trilogy would have been a figure previously frozen from Revenge of the Sith. In an interview with Lucas from Bantha Tracks in 1980 Lucas was asked what the third SW trilogy was about and he said that "It deals with the character that survives Star Wars III and his adventures."

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http://starwars.wikia.com/wiki/Sequel_trilogy