Confrontation on Mustafar (Revenge of the Sith)

Darth Vader: You turned her against me!

Obi-Wan Kenobi: You have done that yourself!

Darth Vader: You will not take her from me!

Obi-Wan Kenobi: Your anger and lust for power have already done that! You have allowed this Dark Lord to twist your mind until now…until now you have become the very thing you swore to destroy!

Darth Vader: Don’t lecture me, Obi-Wan! I see through the lies of the Jedi! I do not fear the Dark Side, as you do! I have brought peace, freedom, justice, and security to my new Empire!

Obi-Wan Kenobi: Your new Empire?!

Darth Vader: Don’t make me kill you!

Obi-Wan Kenobi: Anakin, my allegiance is to the Republic, to democracy!

Darth Vader: If you’re not with me, then you’re my enemy!

Obi-Wan Kenobi: Only a Sith deals in absolutes! I will do what I must!

Darth Vader: You will try!