Darth Vader's First Kill

Let's talk about Darth Vader's First Kill. Specifically, the betrayal and murder of Master Jedi Mace Windu.

Anikin Skywalker understood that Palpatine was a Sith Lord. He had told Master Windu as much. And had received assurances that if he was correct, he would have proven himself, and earned the trust he'd sought for so long.

From palace vid records, we learn that Mace Windu then proceeded to confront the High Chancellor and place him under arrest. Palpatine, of course, would not go without a fight. During this fight, Master Windu's fears were confirmed. Palpatine was indeed a Sith Lord. A Sith Lord would never allow himself to be captured. And if he did, there would be a very high probability that he would escape. The only way to deal with a Sith is to kill them out right. They are far too dangerous to allow them to exist.

It was during this fight that Skywalker began to plead for Palpatine's life. Master Windu tried to explain to him that the Sith couldn't be allowed to live, but the presence of the Sith Lord drew too much of his attention, and he wasn't able to make a proper argument. Knowing that Mace was a Jedi Master, knowing that by revealing the identity of the Sith he'd earned the council's trust, and knowing that Palpatine was a Sith, Skywalker chose to side with the Sith.

Taking advantage of the trust Master Windu had recently placed in him. He struck out and killed him. In that moment of betrayal, he became Darth Vader. And that isn't the last time he worked for years to gain someone's trust just to betray them. Vader is so ruthless that he did the very same thing to the Emperor. Though, thanks to his young Jedi son, not for the selfish reasons he had intended, nor in the manner he'd planned.