You Have Forgotten Your Place, Lord Vader! By Taking This Boy As Your Apprentice, You Have Betrayed Me! (Star Wars)

[The Rogue Shadow flies to the Executor. Starkiller stands by Darth Vader's side.] 
Darth Vader: The Emperor's fleet has arrived. 
Starkiller: You have lured the Emperor to us... When do we strike? 
Darth Vader: I did not summon him. 
[The door opens and the Emperor appears. Starkiller turns and is suddenly impaled from behind by Vader's Lightsaber.] 
Darth Vader: His spies followed you here. 
[He falls as the Emperor approaches.] 
Darth Vader: What is thy bidding, my master? 
The Emperor: You have forgotten your place, Lord Vader. By taking this boy as your apprentice, you have betrayed me.