As the fifth season opens, Elena, after a passionate summer with Damon, heads to college nearby with Caroline as her roommate. Plus, a terrifying appearance by Silas (PAUL WESLEY).

A fellow Whitmore student named Jesse (KENDRICK SAMPSON) gives Elena some intriguing information about Professor Wes Maxfield (RICK COSNETT). Damon asks for help finding Stefan.

When Elena and Katherine have the same dream that Stefan is in danger and desperately needs their help, they convince Damon to help them find Stefan. However, their plans are thwarted by a mysterious young woman named Tessa who seems to know everything about Stefan's history. In flashbacks to a distant time and place, Tessa reveals the shocking secrets in her past and what she has planned for the future. She also has a disturbing message for Damon about his own future. Silas forces an unwilling accomplice to help him search for Katherine, leading to a confusing and life-threatening situation for Matt. Finally, Silas reveals the reason he's determined to find Katherine, and Damon and Elena face a disturbing new reality.

On campus, Elena is touched by a sad and secretive student named Aaron. Elena and Damon attend the Whitmore Historical Ball dressed as Anne Boleyn and Henry VIII. At the ball, Elena shares a dance with Dr. Maxfield, who has a disturbing message for her. Caroline's evening at the ball takes her from happiness to heartbreak. Meanwhile, Nadia reveals her surprising history to Katherine, and Damon tries to make a deal with Silas. But when Silas demands that Damon commit an unthinkable act, it leads to a violent confrontation.

The power of doppelgangers.... While Elena and Damon try to explain Amara's situation to Stefan, Dr. Wes Maxfield gives Katherine some deeply disturbing news. Nadia shows up at Caroline's dorm room searching for Katherine. After a surprising conversation with Amara, Jeremy and Bonnie share a glimmer of hope. Silas fails to keep a promise, causing Damon to turn to Tessa for help with his new plan, and Stefan makes a heartbreaking confession to Damon and Elena.

At Whitmore College, Elena and Caroline decide it's time to throw a big party, but their plans are interrupted when Jesse suddenly needs Caroline's help. At Elena's request, Damon comes up with an effective method to get Wes to answer his questions. At the party, Elena finds that she and Aaron have a lot in common, and Caroline grows more concerned about Jesse. Meanwhile, Katherine does a favor for Matt and manages to get through to Stefan, who is still struggling to overcome the events of the summer. Finally, Bonnie does her best to cope with her new reality, and Damon makes a terrifying discovery about a secret society.

Damon realizes Elena is in danger and enlists Stefan's help to find her. The brothers pay a visit to Aaron, and Damon shocks Stefan by revealing his first-hand knowledge of Aaron's family. In an attempt to stop Damon, Dr. Wes unleashes his secret weapon, forcing Damon to deal with a part of his past he thought was gone forever, as well as the consequences of his decades-long plan for revenge. Meanwhile, Elena is horrified by Dr. Wes' confessions about the dark history of Whitmore College and his own ultimate goal. Finally, a frantic Katherine turns to Matt for help, until she realizes that Nadia may be the one who can solve her problem.

Back to Katherine's early life 1490, Nadia helps her mom with a fighting plan.

Damon tries to get back together with Elena, however, Katherine has a plan and attempts to take Elena's body permanently. Tyler is upset with Caroline and Matt is used by Katherine. Enzo finds Damon and they decide to become a team again.

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.

As Damon's behavior escalates from destructive to deadly, Stefan begins to regret their last conversation and decides to track Damon down and intervene. For reasons of her own, "Elena" volunteers to come along. Dr. Wes enlists the Travelers to set a trap that will once again test Damon's friendship with Enzo. After a heart-to-heart talk with Nadia, Matt enlists Caroline and Tyler's help to protect Elena, leading to a violent confrontation. Later, when Stefan tries to comfort a dejected Caroline, their conversation leads to a horrifying realization.

While Nadia remembers her centuries-long search for her mother, Stefan, Caroline and Matt come up with a desperate new plan to save Elena's life. For the second time, Bonnie and Jeremy must turn to Liv for help. Damon baits Tyler into a nasty confrontation, then takes off to seek revenge on Dr. Wes. Caroline and Tyler come to a new understanding. Finally, Bonnie learns of a terrifying secret that will threaten the lives of all her friends.