<P> Katherine and Stefan bring Damon back to Mystic Falls and Katherine arranges immediately to meet Nadia . Katherine is happy because, despite that her plan to kill Damon did not work, she had a moment with Stefan . She stops smiling when Nadia tells her that she was bitten by Tyler Lockwood . </P> <P> Damon wakes up chained on the Salvatore house's basement . Stefan is there and Damon tries to warn him that because of his cravings, one day he will kill him but Stefan tells him that they will find a solution . Damon points to Stefan that "Elena" provoked him to feed on her and then she kicked a stake towards him so he will kill him . Stefan does not believe that Elena would want that, he locks Damon up and gets upstairs where Caroline is . The two of them discuss what happened between Stefan and "Elena" and Caroline also tells him about Nadia and Matt and the text he sent to her . From Matt's text, who used "K" and not "E", they put the pieces together and they realize that Katherine is in Elena's body . </P> <P> In the "No Exit" episode we can hear the songs: </P> <Ul> <Li> "Radioactive" by Imagine Dragons </Li> <Li> "You Belong Here" by Leagues </Li> <Li> "Fleur Blanche" by Örsten </Li> <Li> "Poisonous Spider" by Company </Li> </Ul>

When does katherine pierce leave elena's body