Determined to protect his sister, Jeremy makes a decision that will change everything. In the harsh reality of the present situation, Elena longs for simpler times when her parents, Grayson and Miranda, and Aunt Jenna were still alive and her biggest concern was her relationship with Matt. Stefan and Damon leave Mystic Falls together on a mission, but soon split up when Elena needs one of them. Caroline and Tyler are forced to make a life-changing decision. Finally, Bonnie makes a secret deal that has heartbreaking consequences.

Damon goes with Elena and Bonnie to visit Whitmore College, where Professor Shane is taking over the Occult Studies classes formerly taught by Bonnie’s grandmother. At a fraternity costume party, Damon takes advantage of the wild scene to give Elena a lesson in choosing a victim. Rebekah’s attempt to buy Matt’s forgiveness falls flat, but she is intrigued by unexpected news from Klaus. When Stefan questions Klaus about Connor’s motives, Klaus reveals a long-ago encounter with a powerful group of vampire hunters, but it’s Rebekah who delivers the information that stuns Stefan.

Appearing unexpectedly at Mystic Falls High, Rebekah wastes no time trying to force Stefan, Elena and Caroline to answer her questions about the search for a cure, leading to a bombshell piece of information from Elena. When Bonnie’s father, Rudy Owens, accepts the role of Interim Mayor, he makes it a priority to protect his daughter, who isn’t at all comfortable with the role he suddenly wants to play in her life. Professor Shane continues to encourage Bonnie to believe in her powers, but he soon finds himself in danger when he reveals too much to the wrong person. Later, Caroline does her best to comfort Tyler after a violent confrontation. Meanwhile, at the lake house, Damon and Matt train Jeremy, trying to raise his game as a hunter, but Klaus is impatient with their progress and intervenes to speed up the process.

Damon and Elena try to help Stefan through a confusing time, which ends up taking Elena on an emotional journey. Caroline makes an effort to know Jesse better.

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.

Bonnie has an unsettling encounter with Luke, and learns more about his family history. The Travelers' leader, Markos, arrives in Mystic Falls.

With Homecoming around the corner, Elena invites Liam to attend a party at the corn maze with her. Instead of attending the homecoming festivities, Caroline is preoccupied after Stefan shows up unexpectedly and needs her help cleaning up a mess created by Enzo. Heeding Elena’s advice to be more social, Alaric reluctantly attends the party, but a devastating accident quickly leaves him and Jo rushing to save lives. Elsewhere, Tyler finds himself in a dangerous position when his werewolf curse is put to the test, and an emotionally embattled Stefan comes clean to Caroline about his intent to move on from Mystic Falls. Lastly, Damon and Bonnie make an important discovery that affects their quest to get back home.

When Liv and Luke’s father arrives to town to celebrate their birthday, they try and convince him to let Jo and Kai take their place in the merge ceremony. After Tyler finds out that the merge is happening sooner than he expected, he urges Liv to let him talk to her father. Meanwhile, after Caroline’s plan to cure her mother takes an unexpected and devastating turn, Elena, Stefan and Damon gather at the hospital, while Jo attempts to save Sheriff Forbes’ life. Lastly, with the merge set to take place, Damon’s risky plan quickly sends things spiraling out of control, forcing one of the twins to take matters into their own hands.

As Alaric and Jo reluctantly participate in their bachelor and bachelorette parties, Damon and Elena discuss the ramifications from an impulsive offer that Damon makes. Unsure of what to do, Elena turns to Bonnie and Jo for advice, but is left conflicted when Bonnie raises some unanticipated concerns. When Enzo realizes Lily is on a dangerous downward spiral, he asks Stefan to help intervene before it’s too late. Lastly, fed up with the supernatural threats that plague their town, Matt takes his frustrations out on Tyler, while Alaric considers a life-changing piece of advice.

As Julian and Lily throw a party to celebrate Mary Louise and Nora's anniversary, Stefan and Damon set in motion a risky plan to eliminate a new threat posed by Julian. Meanwhile, following a major revelation uncovered by Valerie, Caroline is forced to face her new reality, even as it threatens to destroy her relationship with Stefan. Finally, determined to do what's best for her family, Lily makes the most difficult decision of her life.

In order to lure a vengeful vampire hunter named Rayna Cruz away from his friends in Mystic Falls, Stefan heads to New Orleans, where Valerie has learned of a safe house that can protect him. Once there, he comes face to face with Klaus Mikaelson, who soon becomes suspicious of his old friend's unexpected arrival in his city.

Meanwhile, Enzo, who is working on behalf of a mysterious organization called The Armory, approaches Damon and Bonnie with a plan that could protect Stefan from Rayna. Finally, after learning that Alaric has decided to leave for Dallas with the twins immediately, Caroline offers to accompany them on the trip and finds herself contemplating her own future in Mystic Falls.

The crossover continues on The Originals S03E14 A Streetcar Named Desire (II).

When Damon's risky attempt to save Bonnie takes an unexpected turn, the consequences of his actions forces everyone to band together to help her pull through. Meanwhile, when a new threat leaves Caroline's life in jeopardy, Stefan makes a rash decision that ultimately forces them to face the fallout from their relationship. Elsewhere, Enzo tries to hold it together as he painfully watch Bonnie in the fight of her life, while Matt takes matters into his own hands to save one of his closest friends.

Tasked with finding a mysterious artifact, Damon’s latest mission takes him to Texas where a violent run-in with Peter Maxwell leads to a surprising revelation. Meanwhile, after gaining the upper hand in their fight to save Damon and Enzo, Stefan and Alaric team up and uncover the origins of the mysterious force they’re up against. Finally, Matt returns to the fray after his past and present collide in an unexpected way.

Sybil enacts revenge on Damon by putting him in a catatonic state. Caroline and Bonnie enter Damon’s mind and run into familiar faces from the past, only to discover Stefan is the key to Damon’s fate. It’s a race against time for the bell as both Sybil and her sister Seline jockey for its control.

Damon and Stefan must join forces against Cade in order to save Elena’s casket. Meanwhile, Caroline and Alaric deal with their daughters’ burgeoning magical powers.