By the Light of the Moon

As the full moon approaches, Caroline helps Tyler prepare for his transformation. Stefan asks Katherine to prove that there is good in her, and she advises him to ask Isobel for help in finding Klaus. Bonnie seeks Luka's help to destroy the moonstone; they cast a spell, but Luka gives the moonstone to his father. Jules, a friend of Mason, arrives in Mystic Falls looking for him. Damon and Alaric try to trick her into having a drink mixed with wolfsbane. She reveals that she is a werewolf and tells Damon that he has been marked. Elijah makes a deal with Elena: she has to keep herself safe from Klaus (so that Elijah can use her as bait to kill Klaus) and in return, Elijah will protect her friends and family and free Stefan from the tomb. Caroline reunites with Tyler. At the Salvatore mansion, Jules, in wolf form, tries to attack Damon but instead bites Rose's shoulder, which becomes infected.

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