I think it's important to stress that the original trilogy is Luke's story rather than Vader's.
Exactly.
Star Wars and
Empire were about Luke. I'm willing to bet anything that the name "Anakin Skywalker" wasn't even invented until
Jedi was pitched. Unless, of course you can direct me to some Expanded Universe kitsch... but the name was never uttered in any film. Until George Lucas tampered with
Empire in the Special Edition.
I watched
Empire yesterday, and subconsciously erased all knowledge of
Jedi and the prequels, trying to evaluate the story's merits on its own. And when it was over, I found that I had come to a very surprising conclusion. The one thing that ruins
Jedi, and makes it cheapen the entire
Star Wars story overall, is that it says that Darth Vader is Luke Skywalker's father.
"Wait," I hear you say, "wasn't it
Empire that said that?" Actually, no it wasn't. That seems like a pretty big denial of, well, the most famous plot twist in movie history, but bear with me. Throughout Luke's training, Yoda keeps warning him of the Dark Side of the Force, and speaks of its dangers. It is quicker, easier, and more seductive. You get the feeling, long before Luke actually faces Vader, that the Dark Side will throw whatever it has got on you, that it will do anything and use any trick in the book to turn you over. Furthermore, as we learn from Luke's experience in the cave, the Force and the confrontation with the Dark Side, is a very personal experience, different for every single person. Luke thinks his worst enemy is Vader, when it is in fact himself. With that experience, he can go to face Vader bearing in mind that, fearsome though he may be, he is not invincible. Luke has learned to control himself, and that is all that's needed to defeat Vader.
So when Luke eventually does face Vader, he turns out to be a stronger opponent than Vader expected. At this point, I get the feeling that Vader is just a wicked, twisted thug of the Emperor. Everything in the film points to that. He gets his orders from him, and even in the fight, Vader refers to the Emperor as the one who actually wants Luke. Vader is his loyal dog, and he has got orders to win Luke over, no matter what. Luke's resistance is so fierce that Vader must strike him right where it hurts: His heart. We know from the last film, that Luke always wanted to know what happened to his father, who he was and what he did. He has a deep admiration for him, despite having never even seen him. His father, you could say, is Luke's Achilles heel. Vader knows this, because he can read Luke's feelings. This is what makes him all the more dangerous. When Vader eventually says that he is, in fact, Luke's father, this is a calculated stab at Luke's heart that bears both a comforting statement, and a promise: If Luke turns over to the Dark Side, he will have a father, who will raise him as his son - in fact, his disciple as a Sith Lord or whatever.
Think, for a moment, of another film of the same era,
Conan the Barbarian. In the final scene, Conan confronts Thulsa Doom (interestingly, also played by James Earl Jones), who also tells him that he is his father. Everybody, including Conan, knows that this is not true in a biological sense - we've even seen Thulsa kill Conan's father. But by this act, he effectively takes his father's place in Conan's heart. Of course, Conan wants revenge, and wants to kill him, but in order to do so, he must become more powerful than him. This is effectively a father-son relationship. The father is always the son's ideal and point of reference, and all his striving is in order to become a match for him.
I think this is the idea included in
Empire as well. Vader, as the man who killed Luke's father, steps in his place, effectively offering custody over the orphaned boy. He vows to be everything a father could be, striking a chord with Luke, who never wanted anything more. This is he greatest temptation possible for Luke, but he demonstrates his mastery of the Force by denying this offer, and not giving in to this ultimate display of seduction. This makes him both a hero, and a martyr (ever noticed how the antenna he is eventually picked up from looks curiously like a cross?).
However, Vader has established an emotional bond with Luke, and with the use of the Force, he can keep tempting Luke by confusing his feelings. Luke doesn't know if he should believe him or not. At this point, accepting Vader as his father would mean that he would have to follow him. We are not offered any alternative interpretation in the film. The viewer is left with this struggle unresolved for the final installment of the saga.
Effectively, this means that the mother of all plot twists was in fact not a plot twist at all, originally. It was only turned into such by the unimaginative writing of
Jedi. I used to think that both films were conceived and planned together, but if you look at it closely, this simply can't be the case. Obi Wan's explanation in
Jedi is very forced, and only his statement that, "you're going to find that many of the truths we cling to depend greatly on our own point of view" could have saved this, if it would actually have been turned into a plot device that would have helped Luke overcome Vader or the Emperor later on. But as it is, it's just a desperate attempt at tying up loose ends without generating too many plot inconsistencies - which, in my opinion is a failure. Instead of further going the avenue set up by
Empire,
Jedi was turned into a movie about Vader being redeemed by Luke, and trying to make it seem as if the entire saga had been about Vader in the first place. It wasn't. It never was. And I'm sure the original ideas that Lucas had for the prequels did not go in that direction either.