After shutting off her humanity following the death of her mother, Caroline gives her friends an unexpected ultimatum. Not knowing how to handle the new Caroline, Stefan's attempt to intervene sets off a dangerous chain of events, leaving him and Elena in a race against the clock. Meanwhile, after seeking answers from Kai about the prison world, Damon's world is turned upside when he learns some devastating news about his mother Lily. Elsewhere, Enzo finds himself becoming increasingly intrigued by Sarah Salvatore, and Bonnie begins to struggle with the effects of being back in the real world.

With their humanity turned off, Stefan and Caroline begin wreaking havoc at Whitmore, leaving Damon to come up with a risky plan involving Lily. After rushing to help Jo treat victims of Stefan and Caroline's latest killing spree, Elena discovers Jo is pregnant, prompting her to reevaluate her own life as a vampire. Meanwhile, when Sarah boldly turns the tables on an unsuspecting Enzo, he is forced to open up about his tragic past. Lastly, at Scull Bar, a twisted round of karaoke leaves Tyler and Matt in a dangerous situation.