As she faces a new crisis, Katherine remembers the traumatic night in 1490 when she gave birth to the daughter who was immediately taken from her. Stefan lets Elena, Caroline and Bonnie know that Katherine's health has taken a turn for the worse, while Damon Matt and Jeremy discuss some of Katherine's most notorious moments. Nadia comes up with a frightening plan to protect her mother, and Stefan and Elena are forced to help her. Meanwhile, Caroline is mortified when she realizes she forgot to fill Elena in on the latest shocking gossip, then indulges in a little scandalous behavior of her own. Finally, Elena and Katherine share an unexpected moment of connection.

Hoping to help everyone move past recent traumatic events, Caroline convinces Elena and Bonnie to attend Whitmore College's "Bitter Ball" for broken-hearted students. Bonnie is intrigued with a fellow student named Liv, who appears to be dabbling in witchcraft. Tyler starts to worry about Matt's relationship with Nadia. After making a disturbing discovery, Stefan has a frustrating conversation with Damon and Enzo. Dr. Wes struggles to continue his research project with help from a new benefactor named Sloan. Still bent on revenge, Damon and Enzo resort to violence to convince Bonnie and Jeremy to help them, but their plan takes an unexpected and horrifying turn.