Downstairs, Bonnie finds Lucy, and tries to stare her down, but once they touch, Bonnie realizes she can trust Lucy and gives her the moonstone. WHAT?! I hope you're right, B.
Back upstairs, Damon shoves Katherine against the wall and readies himself to stake her as soon as the linkage spell has been lifted from Elena. Speaking of... it's then that Lucy arrives -- moonstone in hand. She informs Katherine that the room-sealage spell has been lifted. Once she gets Katherine's confirmation that their score is settled, Lucy hands KaKa the moonstone. But wait! It must be transmitting some bad juju, because when Katherine touches it, she gasps for breath and falls to the floor -- moaning and groaning. Lucy scolds Katherine for not warning her that another witch -- particularly a Bennett witch -- is involved in the intrigue, but Katherine's not up for explanations. As he watches Katherine suffer, dawn breaks over Stefan's marble head, so he yells, "Wait. Elena!" but Lucy informs him that Elena's fine. The Katherine/Elena linkage has been broken, and she'll heal quickly with Bonnie by her side. As Lucy apologizes to the boys for her involvement, Katherine loses consciousness and the fans go wild.
In the study, Caroline lies to Carol Lockwood that Sarah was drunk and just tripped and ended up all dead. Carol seems to believe her, but when Ty informs the ladies that Sheriff Forbes is there, Carol leaves Caroline with a warning to wait for her mother. "She's going to want to hear this story from you." Once Tyler is alone with Caroline, he asks why she lied. Caroline, who has already stashed an unconscious Matt away in her car, is playing the sweeper in this episode, and pretty much admits it, but when she hints that she's aware of Tyler's lycanthropy, he sneers -- clearly thinking she has no idea what's what. Caroline proves herself by half asking/half pointing out that his stab wound has healed. Ty's all, "How did you..." as we cut to the mansion's exterior.