Why didn't Vader just let Luke kill Palpatine?

Luke had grown to powerful for Vader to turn him to the darkside by himself. He needed Sidious to help him, and letting Luke kill him would have been stupid. He also needed to make sure Luke was loyal to him before they killed Sidious, otherwise Luke would have killed Vader too, and probably gone back to his friends.

 

Simple. Luke would simply try to "leave" after that. In order to rule the galaxy as father and son, he had to have training by Palps, then kill Palps, then get trained by Vader. It's that simple.

 

I don't think Luke could kill Vader - GL says Anakin is the only person powerful enough to destroy the Emperor, so he's not going to be cut down by a trainee. But blocking Lukes blow serves several functions: it protects Luke from the Emperor (Palps wouldn't have let Luke strike him - look at how he force-lightnings Mace right out a window!); it allows Vader to turn Luke, making Vader Luke's master and so the two of them can command the Empire together - Anakin hates politics, so Luke would be the politician!; Vader was hedging his bets - he was still learning from Palps, and might have needed convincing about Luke's strength.

 

Did you guys miss everything Palpatine said in this movie...

Did you not realize that the Emperor is the master of lies, deceit and manipulation? Just because he says something does not make it true. For example, he says ?I am unarmed? or ?I am defenseless? and we know that is not true. Vader is his defense and he is certainly armed with Force lightening. He also says ?Strike me down with all of your hatred and your journey towards the dark side will be complete.? Again, not true. Obi-Wan killed Maul (and I?m sure he was at least moderately angry when he did it) and he did not turn. That one act is not enough to make Luke turn. The Emperor was trying to confuse Luke and make him ignore his Jedi training.

Vader didn't want Luke to fall to the darkside. He was in a way preventing Luke from giving into anger and killing Palpy. Palpatine knew Vader would protect him, but he did not know why.

Where the heck did you get that from?! Vader wanted Luke to turn and kill the Emperor. Vader did the one thing that brought Luke the closest to the dark side: he mentioned turning Leia to the dark side.

Vader is very torn in this movie. He wants to save Luke, but at the same time he is hiding this from both Luke himself and the Emperor.

Again, I disagree. Vader was carrying out the Emperor?s orders and was doing exactly what he was told. I don?t believe that Vader decided to save Luke until he was watching the Emperor killing him. It was obvious in the way that scene was shot. Vader was looking at Luke and then the Emperor and then back and forth again. He was obviously deciding which way to go.

 

I always thought Luke was trying to hit Vader.
Although the script says-
"Luke can resist no longer. The lightsaber flies into his hand. He
ignites it in an instant and swings at the Emperor. Vader's
lightsaber flashes into view, blocking Luke's blow before it can
reach the Emperor. The two blades spark at contact. Luke turns to
fight his father."
It seems
-Luke ignites his saber.
-Vader ignites his saber.
-Luke swings, Vader Blocks. I don't have a clue who he was swinging at though.

 

There was a question as to why Lord Vader did not kill Darth Sidious in the 19 years between Eps. III-IV, and I would like to take a stab at it. After his immolation on Mustafar, Lord Vader was simply not strong enough to dethrone Darth Sidious. After all, "He is more machine, now, than man." (Obi-Wan) But 19 years of looking back and knowing that the life he now leads is because of the manipulation of Sidious, resentment begins to grow. The seed for dethroning Darth Sidious was already there in Ep. III before his duel with Obi-Wan, in which he refers to "my new empire..." He begins to allow himself visions of granduer, which Obi-Wan deftly demolishes with his crippling of Anakin. Which is why Vader was so enthusiastic about fighting Obi-Wan again aboard the Death Star.
As to why Vader blocks Luke's attempt to slay Sidious, I can only agree with a past comment that Vader wanted to assume the more dominant role of the two ruling Sith. To allow Luke to kill Palpatine would have meant that he was allowing Luke to be his master, in a way. I believe that he wanted to kill Palpatine, but still needed Luke's help. He wanted to use Luke as a minion, under his control. Luke would have to be turned first.

 

It is mentioned in the Novel that Vader was worried that without Palpatine to help fully emerge Luke in the ways of the Dark Lord of the Sith that Luke could go back to being good.

It's in the novel, but you know about the novel

Aiel, you get the prize for being the only one to answer this question correctly. This is exactly the reason why Vader blocked Luke's attempt. Vader knew Luke needed both his, AND Palpatine's tutelage to ensure he would fully turn to the darkside. Once his turn was complete Vader, along with Luke, could then kill the Emperor, and rule as Vader had planned from the outset.

 

Vader didn't want Luke to follow in his footsteps and become a sith lord. Anakin was fighting his way back to the surface and Vader was on his way out. There was an internal battle within Anakin/Vader as well as the saber duel with Luke.

 

if luke would of killed palpy wouldnt he have taken his step toward the darkside

 

Lets just put it this way, if you had a son who was being held at gun point would you save him? Yes you would, it is the same reason Vader saved Luke

 

Vader was still loyal to his Emperor at this stage and the Emperor knew this. Vader was conflicted: "I must obey my massster!"

 

Vader of ROTJ was a very different Vader from ESB and ANH. No longer was he the confident, arrogant, badass from IV and V. In fact I believe in many ways in ROTJ Vader reverted back to the conflicted Anakin Skywalker of ROTS.

By the time of the Death Star Lightsaber battle, he was very conflicted. Similar to his feelings in ROTS when he was torn between the Jedi and the Emperor, in ROTJ he was again torn between...well...the Jedi(Luke) and the Emperor.

When Vader was fighting Luke, he wasn't giving it his all b/c he was still very conflicted in his emotions. It wasn't until he watched the Emperor attack Luke that he FINALLY made his choice--evoking memories of a time when he made a fateful decision resulting in the death of a certain purple lightsaber wielding Jedi...

Why didn't Vader let Luke kill the Emperor? The same reason he didn't let Mace kill the Emperor 20 years prior...HE WAS CONFLICTED.

 

Yeah, Vader wasn't sure of his loyalty yet. He didn't want Palpatine dead. Not that Palpatine was actually in any danger, I am sure. He probably had a plan B like "Woah, I didn't actually think you would do it,"

 

I can't find my ROTJ DVD

 

It's a movie. Enjoy it! That scene is just freaking awesome. Two lightsabers crashing into each other with the evil grin of the Emperor. Fantastic moment in Star Wars cinema. Are you kidding me? Father vs Son. That's drama and conflict. It's great.

 

Yeah Vader knew luke wasnt stroung enough

 

Vader had been waiting 20+ years to kill Sidious. That's the very thing that gave him reason to live after he lost everything, get all the knowledge and power that he could, then kill his master. He wanted the satisfaction of killing Sidious himself

 

Though many of you have made good points, I think you have missed one essential probability: Palpatine was not counting 100% on Vader for defense, just as he wasn't counting 100% on Anakin to defend him against Mace. (OK, I know there's a huge debate in ROTS/PT about whether Palpatine allowed Mace to beat him. ) Had Anakin/Vader not brought his saber to Palpatine's defense, I think Palpatine was ready to blast away. If he could blast the saber from Yoda's hand, an unsuspecting Luke surely would've lost his weapon. Anakin knew that Palpatine was never really defenseless.

If Vader had not parried Luke's blow, what would have happened? Palpatine blasts the saber from Luke's hand, then either a) he kills Luke, b) he kills Vader and then goes back to work on turning Luke (or orchestrates a scene where Luke kills Vader) or c) kills both of them. In any case, he would know that Vader was no longer to be trusted as his whipped Sith apprentice - the very fact that caused him to ignore Vader while toasting Luke, allowing Anakin to return from the dark side unnoticed.

 

Good point. Palpatine also knew Vader was keeping his knowledge of Luke to himself in ESB before the hologram transmission. So Palpatine did not trust Vader. In ROTJ when Vader visits Palps and mentions that his son is on Endor, Palpatine was untrusting of Vader and short with him as well. Palpatine needed a plan B, because Vader was conflicted and was not to be relied apon .

The conflict in Vader obviously made him do his "duty".

 

vader was and had every intention of killing luke but when luke beat him and palpatine started shocking luke with force lightning he couldnt stand listening and hearing his son hurt and destroyed palpatine and through his love of his son he learned the shaman of whills so he could keeb his identide in the netherworld of the force

 

true but mabee Vader wanted to kill palps himself.. When he was tryin to get luke to join him and kill the emporer, mabee he just ment "stand back and take notes while i go kill the emporer my son"

 

I agree, luke was probably to powerful for Vader to handle on his own. so he would have needed sidious to help.

remember Vader only turns to the lightside when sidious is shooting lightning at luke.
Up until that moment greed and a lust for power was still on his mind.

 

Vader had no intention of killing Luke. He may of attacked him without Luke's saber ignited and thrown his lightsaber at Luke but that was to test Luke and make a point, at no time was he trying to kill Luke. Vader was testing him. I thought that point was common knowledge.

 

The Novel Dark Lord, spells this out nicely. Your post was spot on!