J.W. Rinzler, the famed Star Wars and Indianna Jones doumentarian, is preparing a new book chronicling the 30th anniversery of The Return of the Jedi. In it Rinzler has this quote attributed to Lucas, which was pulled from a confrence call.
“Well, anyway, Luke’s father gets subverted by the Emperor. He gets a little weird at home and his wife begins to figure out that things are going wrong and she confides in Ben, who is his mentor. On his missions through the galaxies, Anakin has been going off doing his Jedi thing and a lot of Jedi have been getting killed—and it’s because they turn their back on him and he cuts them down. The president is turning into an Emperor and Luke’s mother suspects that something has happened to her husband. She is pregnant. Anakin gets worse and worse, and finally Ben has to fight him and he throws him down into a volcano and Vader is all beat up. Now, when he falls into the pit, his other arm goes and his leg and there is hardly anything left of him by the time the Emperor’s troops fish him out of the drink. Then when Ben finds out that Vader has been fished out and is in the hands of the Empire, he is worried about it. He goes back to Vader’s wife and explains that Anakin is the bad guy, the one killing all the Jedi. When he goes back his wife, Mrs. Skywalker has had the kids, the twins, so she has these two little babies who are six months old or so. So everybody has to go into hiding.”
It’s interesting how close this synopsis is the Revenge of the Sith. It almost makes one wonder what would have happened if the prequels were produced immediately following the success of Jedi.