Careful, residents of Mystic Falls. This is Katherine, not Elena, attending a party on the episode "Masquerade."
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Damon and Alaric are ready to kill. They plot to take down Katherine on the episode "Masquerade."
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Caroline is coming into her own as a vampire. Even Damon has to be impressed by how strong she's become.
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Damon looks downright dashing in this shot from "Masquerade." The vampire sure knows how to dress up, doesn't he?
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Women may prefer to see Stefan's face, but he goes with a mask in this scene from "Masquerade." He's attending a ball.
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That's not Elena with Stefan. It's Katherine, as she accompanies her old crush to a masquerade ball.
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The Vampire Diaries Season 2 Episode 7 Quotes

You aren't gonna kill Katherine... I am.

Stefan

Tell Damon and Stefan to give me the moonstone or I will rip this town apart until it rains blood.

Katherine