While You Were Sleeping

Elena has a nightmare about having her body taken over and wakes up to find her dorm empty. Stefan explains they had to lock her in her dorm after she'd been infected by the virus. Her first instinct is to call Damon but at the same time, Damon is trying to figure out how to tell Elena that he killed Aaron and also infected with the same virus. Elena calls Damon while they are both trapped, but he doesn't tell her. While going through Dr. Wes' files, Caroline discovers that Dr Wes combined the werewolf venom from Nadia's blood with the vampire killing virus, and is surprised when Enzo appears, claiming to have an antidote for the virus, but needs Stefan in order for her to get it. Bonnie works with Liv on teaching her spells. Elena reads her diary that Katherine wrote in and hallucinates Stefan with Katherine and stopping him from doing anything else. Damon shows up in her hallucination but she snaps out of it as blood drips from her nose. Stefan, Caroline, and Enzo go to see the Travelers who have the antidote for Damon's virus and are working on one for Elena's. They want to find another Stefan doppelgänger. They perform a spell on Stefan as well as drain some blood. Elena continues to hallucinate and imagines Aaron being dead. Luke, Elena's 'friend' shows up and she almost turns him, but instead compels him to find Bonnie. Bonnie and Liv show up where Elena is unraveling and stabs her, telling her to drop the seal on the dorm. Damon shows up and gives her Stefan's blood and tells Elena about killing Aaron. Enzo shows up with the antidote for both of them. Caroline and Enzo volunteer to do what the Travelers want and kill the other doppelgänger, because they only want one alive. Luke shows up in Liv's dorm room, revealing they have ulterior motives behind everything (Liv already knows magic and Luke wasn't being compelled). At the end of the episode Elena and Damon both agree they're bad for each other, end things, but then they sleep together.

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