WELCOME BACK, SENIORS - On the first day of their senior year, Elena, Caroline, Bonnie and Matt are still reeling from recent events, while Tyler seems to be enjoying everything a little too much. Damon is annoyed by a new houseguest, and everyone is surprised by the arrival of a new student in Alaric's history class. Matt asks Bonnie for help when he realizes he made a serious mistake. Meanwhile, Stefan continues to carry out his latest assignment from Klaus. Steven R. McQueen also stars. Rob Hardy directed the episode written by Julie Plec & Caroline Dries.
Elena is frustrated by her helplessness, so she convinces Alaric to teach her about protecting herself from vampires. Mikael wakes up and bites Katherine. On the first day of school, Bonnie and Jeremy are having issues since Jeremy keeps seeing Anna. Klaus' sister, Rebekah, moves in with the Salvatores and attends school. Matt continues to see the ghost of Vicki, and she convinces him to perform a ritual that allows her to come and go from his world as she pleases. She says a witch from the other side promised her that if she killed Elena she can come back forever. The gang attends a bonfire, where Elena and Alaric try to capture Stefan. Tyler feels beholden to Klaus since Klaus essentially made him who he is. Elena saves Stefan from a fire after Vicki tries to kill Elena in Alaric's van. Vicki is eventually restored back to the other side by Bonnie while Damon goes home, where Mason Lockwood appears in front of him.
A SENIOR PRANK NIGHT TO DIE FOR - Despite all that has happened, Caroline is determined to see that Elena, Bonnie, Matt and Tyler all enjoy a traditional Senior Prank Night before the school year begins at Mystic Falls High School. However, when uninvited guests show up, it doesn't take long for the evening to take a deadly turn. Damon convinces Jeremy that he can use his new connection to the other side to help find a way to defeat Klaus. Finally, Klaus deepens his hold on Stefan and uses him for increasingly violent and dangerous purposes. John Behring directed the episode written by Michael Narducci.
A senior prank night takes a deadly turn when Klaus finds out that Elena is still alive. Klaus threatens Elena by feeding Tyler his blood and kills him. He tells Bonnie that if she doesn't find a way to create hybrids, Tyler dies. He also tells Stefan to feed on Elena. Stefan tries to stop his urge, but Klaus makes him turn off his emotions and feed on her. Klaus finds out that Elena's blood is needed to create more hybrids. Meanwhile, Katherine and Damon go on a road trip to find a way to kill Klaus. Katherine remembers that Pearl told her about Mikael, the vampire hunter who was also a vampire. Matt, in an attempt to connect with Vicki, commits suicide. In a vision he sees her, and she tells him she can come back to life and has a message for Bonnie. Elena is in the hospital while a nurse, compelled by Klaus, takes her blood. Klaus is waiting to abduct Elena, but he flees when Damon tells him that Mikael is coming. Damon then saves Elena. Moments later, Stefan returns. Jeremy and Katherine find Mikael's tomb and watch as he opens his eyes.
FAMILY TIES - Still in Chicago, Klaus (Joseph Morgan) uses Gloria (guest star Charmin Lee), a witch he knew long ago, to help him track down missing information that will explain why his plan isn't working. Gloria's spells reveal intriguing glimpses of the truth, but she soon realizes she needs Stefan's (Paul Wesley) knowledge to complete the puzzle. When Stefan suddenly finds himself in danger, help comes from a surprising ally. Back in Mystic Falls, a frustrating new enemy pushes Damon (Ian Somerhalder) over the brink and he lashes out in a way that will have lasting consequences. Caroline (Candice Accola) struggles with her own emotional issues, even as she tries to help Elena (Nina Dobrev) face her feelings. Jeremy (Steven R. McQueen) makes a brief but disturbing breakthrough with one of his ghostly visitors, leaving him more confused than ever. Finally, Bonnie (Kat Graham) has a strange encounter that will affect everyone. Matt Davis also stars. Wendey Stanzler directed the episode written by Brian Young.
In Chicago, Klaus uses Gloria the witch to find out why his hybrids aren't turning out the way he planned and Gloria discovers that Stefan is hiding the fact that the doppelgänger is still alive. She tortures Stefan, but Katherine saves him. Back in Mystic Falls, Damon changes his attitude and kills Alaric but Alaric comes back to life. Damon then tries to kill Bill. Caroline saves her father by giving him her blood and has a confrontation with Damon. Meanwhile, Bonnie returns to Mystic Falls and Jeremy tells her about seeing his ex-girlfriends as ghosts. Stefan also tries to find out what Klaus and his sister Rebekah are running from. The answer turns out to be Mikael. Katherine steals Elena's necklace that can contact the Original Witch and teams up with Damon. Klaus brings Stefan back to Mystic Falls to find out what he is hiding.
