2.04 - Memory Lane

Stefan is shocked that Katherine appears again to him as her and scares Elena, claiming she loves him and wants him back. He tricks Katherine to be chained and is prepared to torture her with verbena, but she proves prepared and continues her story how she tricked and betrayed the Salvatore's, the Lockwood's and hence both vampires and werewolves. Mason proves himself a dangerous adversary to Damon and resists telling Tyler about the family curse, but finally sneers it's triggered irreversibly by homicide. Matt is totally turned off by Caroline.

Source: IMdb