The fourth season ends on graduation day when ghosts overrun the town and try to settle old scores and fulfill their supernatural destinies. Meanwhile, Elena makes a decision about the Salvatore brothers and confronts Katherine; and Stefan discovers a horrifying secret about Silas.
Caroline tries to distract Elena from her new obsession; Sheriff Forbes tells Stefan and Damon that someone has been attacking patients at the hospital; during a violent wind storm, ghosts appear.
In hope of turning Elena’s humanity back on, Damon and Stefan provoke her in a new, brutal way; Rebekah receives unsolicited advice from Matt; Katherine is suspicious of an offer from Bonnie.
A mysterious tip brings Klaus back to the town in New Orleans that he and his family built; Elijah learns that a powerful witch has taken Hayley; Stefan and Damon pursue their plan for Elena; Katherine makes a revelation to Rebekah.
As Elena and Rebekah pursue Katherine, Elena runs into Elijah; Damon is unsure how to react when Stefan reveals his plan for the future; Caroline reluctantly helps Klaus.
Realizing that Elena needs time away, Damon takes her to New York; Rebekah is impressed with Elena’s secret agenda; Bonnie tries to maintain her grasp on reality.
Everyone is concerned about Elena’s new outlook; Rebekah receives unwanted advice from Damon as they continue to search for the cure; Klaus uses Hayley to get the information he wants and makes an interesting discovery.
Caroline worries about Elena’s state of mind; Damon gives some somber news to Rebekah and is surprised at her reaction; Bonnie reveals the rest of Shane’s plan.
Damon runs into one of the five hunters on the island; Stefan makes a confession to Elena; the stakes change for everyone after new information about the cure is revealed.
Shane leads an expedition to a mysterious island near Nova Scotia, where he believes he can locate a cure. Back in Mystic Falls, Tyler confronts Klaus, which leads to violence that involves Caroline.