Kill or Be Killed

At the Mystic Falls picnic, Mason Lockwood tells Sheriff Liz Forbes that Stefan and Damon are vampires. Liz and her fellow police officers shoot Stefan and Damon. Caroline and Elena reach the Salvatore's before Liz can kill them, but Caroline's identity as a vampire is exposed to her mother. Liz rejects Caroline as her daughter, and Stefan drinks Elena's blood to gain strength. Caroline confesses to Elena that Katherine had threatened to kill Matt if Caroline didn't spy on Elena and Stefan for her; Elena forgives Caroline. Jeremy and Tyler start to bond when Tyler learns that Jeremy knows about the curse. Tyler almost kills a girl, feeling for a second that he wants her to die. He then tells Mason that he wants nothing to do with the curse, and gives him the moonstone. It is revealed that Mason is working for Katherine, who wants the moonstone, and that they are lovers.

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