Not sure where to post this, but what if Rebecca arrives in MF to see if she can get back her necklace.

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According to episode's 6 spoilers everyone is surprised by the arrival of a new student in Alaric's history class. It also says that Damon is annoyed by a new house guest. The episode is titled "Smells like teen spirit". As we saw in the new spoiler pics for this coming episode, Elena is not wearing her necklace. Rebecca will not know she has it. Any thoughts it would be interesting to see.