Katerina

In Bulgaria in 1490 Katherine gives birth to a baby girl only to have her father take the baby away. Back in the present, Elena offers Katherine blood for the truth. Elena learns that as a descendant of Katherine, she is a doppelgänger from the Petrova line. Katherine reveals that she became a vampire so that she could not be used to break the curse. Katherine came to Mystic Falls to try to save herself from Klaus by offering him what he needed to lift the curse: the current doppelgänger, a witch, a werewolf, a vampire, and the moonstone. Bonnie meets a warlock named Luka and his father. Damon and Rose seek information about Klaus from Rose's vampire friend, Slater, but a healed Elijah overhears them. Elijah compels Slater to stake himself. It is revealed that Luka and his father are working for Elijah.

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