Elena Gilbert and her brother Jeremy come to terms with the death of their parents. Elena is popular amongst her peers and the perfect straight A student, but has difficulties hiding her grief from the world. Meanwhile, Jeremy treads on a dangerous path of using drugs to ease his pain. The arrival of new student Stefan Salvatore, however, makes Elena think about romantic possibilities.

As Mystic Falls gets ready for a festival to celebrate the passing of a comet, Vicki continues to recover in the hospital following Damon's attack. Stefan heads to the hospital to try to use his abilities to make Vicki forget who attacked her, but his efforts are cut short by Matt. Meanwhile, at a parent/teacher conference Mr. Tanner tells Aunt Jenna that Jeremy is in trouble and needs immediate intervention.

In a flashback sequence, Stefan reveals the Salvatore family history to Elena. Elena demands that Stefan explain the frightening events that have been happening in Mystic Falls. In flashbacks, Stefan explains how his rivalry with Damon began. Back in the present, Damon impulsively takes control of Vicki’s future, and a confused and frightened Vicki runs away. Finally, Sheriff Forbes and Mayor Lockwood take steps to protect the town.

Jeremy gets a break from the mysterious new history teacher, Alaric Saltzman and introduces Alaric to Jenna. Bonnie is having terrifying dreams about one of her ancestors. Despite Elena’s efforts to smooth things over, Bonnie and Caroline continue to argue over the medallion. When the girls hold a séance to help them decide what to do, the results are stranger than any of them expected. Matt comes to Caroline’s aid when she needs a friend. Damon finally reveals to Stefan the stunning reason he has returned to Mystic Falls.

In flashbacks, Stefan and Damon recall the long-ago actions taken by townspeople including their father, Guiseppe Salvatore, and Pearl, leading to the devastating events that caused the rift in their relationship. In the present, Bonnie's date with Ben takes a frightening turn. Elena helps Stefan as he and Damon race to find the missing journal that belonged to Elena's ancestor. Stefan learns the reason behind Alaric's interest in both the journal and the town's history. Damon discovers that an old acquaintance has returned to town with an agenda he understands.

Stefan helps Elena and Bonnie out of a dangerous situation. Jeremy asks Anna to a party in the woods, unaware that she has her own reasons for wanting to meet him there. When Stefan, Damon, and Elena work with Bonnie and Grams to open the tomb, everyone is shocked by what they discover.

At the Founder’s Day Gala, Elena and Caroline compete for the title of “Miss Mystic Falls” against other girls from town, including Tina Fell and Amber Bradley. Elena is happy to have Bonnie back in town, but Bonnie still has issues to work through. John Gilbert attempts to intimidate Damon, but his plan doesn’t have the desired effect. Damon discovers that Stefan is hiding a dangerous secret that could impact everyone in town.

Founder's Day has finally arrived, and everyone is busy with last-minute preparations for floats and fireworks. Stefan is uncomfortable with Damon's new attitude toward Elena, but Elena is more concerned about repairing her relationship with Jeremy. Jeremy is worried about Anna, but not sure he's on board with her latest plan for the future. While Caroline is enjoying her day as Queen of the celebration, she also tries to help Matt and Tyler get their friendship back on track. Finally, although Damon and Alaric do their best to stop him, Johnathan Gilbert sets a plan in motion that brings Founder's Day to an end amid chaos, destruction and death.

Stefan has his own ideas about Elena’s new plan for the future. While Damon tries to get the truth out of Jules, he asks Elena to keep an eye on Rose, a situation that turns unexpectedly dangerous. Caroline and Matt try to be honest about their feelings for one another, and Tyler’s reaction to Caroline’s generosity comes as a surprise to her... Damon struggles to hide his true feelings when a life-and-death crisis hits him harder than he expected.

Stefan tells Elena about a dark time in his history and the surprising person whose influence changed everything. After getting the truth out of Luka, Jonas makes his feelings clear to Bonnie and Jeremy. Trying to catch Elijah off-guard, Damon arranges a dinner party for him with Jenna, Alaric and Andie, but last-minute information throws Damon’s plan into chaos.