We All Go a Little Mad Sometimes

Elena is hallucinating about the death of Connor, which is slowly driving her mad. Klaus informs the Salvatore brothers that Elena needs to be locked away, because eventually she will try to kill herself. After stealing her away from the brothers, he explains that due to killing the original five hunters, he experienced the same thing and there is no cure. Meanwhile, Shane is hosting an exhibition at the school with Bonnie's help. Damon and Bonnie turn to him for answers. He tells them that Elena's hallucinations are due to a witch's curse and the only cure is for a potential hunter to make a first kill and pass along the last hunter's powers. Jeremy has discovered the beginnings of the mark on him. Stefan goes to break Elena out only to have her attack him and escape. She goes to the bridge where she died and the hunter, Katherine, and her mother convince her to take her own life. She drops her daylight ring into the water. Stefan sends Damon to bring her back. Klaus provides Jeremy with one of his hybrids to kill to complete his transition to a hunter and break the curse in return for a single date with Caroline. This causes tension between Caroline and Tyler, not just because of her having a date with Klaus but also because in Tyler's eyes "[Caroline] sacrificed one friend for another." He feels as if he's the only one in the group that considers the hybrids' safety. The curse is broken just as dawn comes, and Damon saves Elena by throwing them both in the river. He tells Elena that Stefan had been lying to them, but it was all for her. Stefan and Elena sit on the front steps and talk. Elena admits that as a vampire, her feelings for Damon have been magnified, and Stefan tells her he can't do this any more so they mutually decide to split up.

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