In that interview, Lucas said of Vader's history: "It was a whole part of the plot that essentially got cut out. It may be in one of the sequels."
Asked "What's the story?", he said: It's about Ben and Luke's father and Vader when they are young Jedi knights. But Vader kills Luke's father, then Ben and Vader have a confrontation, just like they have in
Star Wars, and Ben almost kills Vader. As a matter of fact, he falls into a volcanic pit and gets fried and is one destroyed being. That's why he has to wear the suit with a mask, because it's a breathing mask. It's like a walking iron lung. His face is all horrible inside. I was going to shoot a close-up of Vader where you could see the inside of his face, but then we said, no, no, it would destroy the mystique of the whole thing.
The back story of Darth Vader, as presented in the Star Wars Official Poster Monthly , issue 2 Star Wars told us relatively little...
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