Damon can't trust Elena's decision to rely on Elijah and the bad blood is brewing between the brothers. Watch a clip from "The Last Day" and see.
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An extended version of the promo for next week's episode of The Vampire Diaries, "The Last Day." What does Damon have in mind?
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The first promo for the April 28, 2011 episode of The Vampire Diaries, "The Last Day." Damon is totally gonna screw this up.
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The Vampire Diaries Season 2 Episode 20 Quotes

Damon: And you're going to die, Elena.
Elena: And then I'll come back to life.
Damon: That is not a risk I am willing to take.
Elena: But I am. It's my life, Damon. My choice.
Damon: I can't lose you.
Elena: You won't.

The problem, Damon...you talk a good game but you don't actually know anything. She'll never forgive you. And never for a vampire...it's a very long time.

Elijah