Later, Caroline reassures Matt that he will not have killed Tyler. She asks about her mum some more, but Matt admits that he doesn't think she knows what to do about Caroline. Suddenly they notice someone at the door and discover Tyler curled up and laying on the porch. Caroline covers him with Matt's jacket and eventually gets him inside. Matt admits that he has enjoyed the last few days with Caroline but adds that he doesn't think he can deal with her being a vampire. He reveals that he already has a tough life but he just wants to live it without dealing with the supernatural as well. When Tyler wakes up, he admits that he should not have returned to Mystic Falls. However, Caroline tells him not to leave again. She admits that Matt broke up with her and Tyler hugs her as she cries. After her suggestion that instead of bailing on her he could thank her for taking care of him, he does. They end up curled up under a blanket together while sitting on the couch.

Elsewhere in the episode, Damon shows Katherine his werewolf bite but decides to leave. She is hurt that he is leaving without saying goodbye and tells him not to depart on bad terms. She insists that she didn't have a choice and had to lure Jenna for Klaus, adding that she chose her life over Jenna's. Damon is angry, though, and points out that Katherine will survive this without a scratch. Katherine points out that she doesn't let love get in the way and Damon tells her to enjoy an eternity alone. He leaves to offer himself to Klaus, but Katherine insists that Klaus won't accept him as his blood is impure.

Down at the quarry - where the sacrifice is being held - Jenna explains that she was tricked into believing Elena was in danger and was captured when she left the house. She reveals that she remembers being forced to drink Klaus's blood, but nothing else. Elena asks if she remembers how people become vampires and Jenna realizes that Klaus killed her. Elena says that everything will be OK, but Greta appears, asking if Jenna is hungry. Elena tries to hit her with a stone but Greta uses her powers to throw her away and surround her with a spelled fire that she can't escape. Greta cuts herself with the stone and, although Elena begs her not to, Jenna is unable to stop herself from drinking Greta's blood. She looks up at Elena, scared, and Elena tells her it will be OK.

Over at the abandoned cottage, Jeremy and Bonnie look through the Grimoires to find a way of stopping Elena becoming a vampire. Meanwhile, Elijah, Alaric and Stefan arrive to speak to Bonnie. Elijah explains that the sacrifice will happen in stages - the werewolf will be killed, then the vampire, and then the doppelgänger. He says that once Elena dies, the curse will be broken and Klaus will become a hybrid. However, this will also be when Klaus is weakest and Bonnie will be able to deliver him to the brink of death. Elijah says he will finish the job. At that moment, Damon calls Stefan and reveals that Jenna has been taken and will be used as the vampire. Inside, Jeremy reveals that he thinks he's found a spell that might help and decides to ask Stefan to bring Jonathan Gilbert's journals for more information. Alaric appears and asks to speak to Jeremy alone.

He explains that Jenna has been taken. Upstairs, Bonnie is willing to kill Klaus now to save Jenna, even though it would mean killing herself. However, Stefan refuses and explains that he has a plan - he will offer himself as the vampire instead. Meanwhile, John arrives at the Salvatore house looking for Elena. Damon admits that Klaus has her and the sacrifice will happen. He adds that he has fed Elena his blood so she will come back to life. John is furious with him but Damon says it gets worse.

Elena asks how Jenna is feeling and she admits that everything is intensified. Elena informs her that vampires can turn off their emotions and says she will not let Jenna be killed. They hear a scream and Jules is brought over and surrounded by fire. She is writhing with pain and Greta explains that she has slowed down the transformation process. Elena reminds Greta that witches are supposed to maintain the balance in nature, but Greta announces that her loyalty is only to Klaus. Klaus appears and begins the sacrifice by handing the moonstone over to Greta. She begins the spell and removes the fire around Jules. Jules groans that everything she did was just to help Tyler.

Jules attempts to attack Klaus but he overpowers her and rips her heart out. Greta pours the blood into the spell, while Jenna admits that she has "failed" Elena. Elena insists that she hasn't and explains that being a vampire has made Jenna's guilt more intense. She tells her that it also makes her stronger, and fast. She says she will get through this and quietly whispers to Jenna that when she gets the chance, she has to run.

Meanwhile, Stefan is about to leave for the sacrifice and tells Elijah to follow with Bonnie later. Elijah calls him "honorable" and Stefan asks if Elijah is too, pointing out that the plan is contingent on that. Elijah promises not to fail him, even though Klaus is his brother. He explains that Klaus killed all of his siblings and his parents and scattered them across the seas so they couldn't be found. Stefan realizes that Elijah is looking for revenge. Meanwhile, Alaric tells Damon that Stefan is going to offer himself and Damon is furious. Alaric notices that something is wrong but Damon claims that he is fine. Later, Bonnie and John explain that they have a spell that could save Elena.

John explains that in Jonathan Gilbert's time, a woman had a sick baby but bound her life force with the child's. When the child died, the mother's life flowed through her and restored the baby's life. John explains that he will not let Elena become the thing he spent his life protecting her against. Bonnie casts the spell on John and Damon, Bonnie and Elijah leave for the sacrifice. Jeremy wants to accompany them, but Bonnie kisses him and casts a spell to make him pass out. Meanwhile, Alaric is furious when he discovers that he is unable to leave the house because of another spell Bonnie has performed to keep him safe.

The sacrifice continues and Elena begs Klaus to let Jenna go, explaining that she doesn't have to die. Elena doesn't want to leave Jeremy without a family and points out that she did everything Klaus asked. However, Klaus realizes that Stefan has arrived and goes to speak to him on top of a cliff. Elena realizes that now that Jenna is a vampire, she has special hearing. Jenna struggles, but eventually works out that Stefan wants to replace her in the sacrifice. Klaus and Stefan return to the women and Klaus asks Elena who she wants to save - and who she wants to die. However, he soon reveals that she doesn't really have a choice and stakes Stefan in the back. He explains that he has other plans for Stefan and needs him alive. Greta removes the fire from Jenna and Elena begins to sob. Jenna says that she knows what she needs to do, and rushes over to bite Greta. However, Klaus stabs her. He lies her down and Jenna looks at Elena, scared. Elena tells her to turn off her emotions so she won't be scared. Klaus stakes Jenna in the heart killing her.

Stefan soon wakes up and, when he sees Elena crying, realizes that Jenna has been staked. He apologizes but Elena tells him to be quiet and asks if the others will kill Klaus. Stefan says they will and Elena smiles grimly. Klaus appears and tells Elena it's time, offering her his hand. She refuses it and walks past him to the sacrificial altar. Klaus thanks her, but she tells him to go to hell. He bites her neck and feeds from her until she falls onto the ground, lifeless. Klaus announces that he can "feel it happening" and begins to transform.

However, Bonnie appears and throws him across the ground. Greta heads over towards them, but Damon breaks her neck. He picks up Elena and pulls the stake out of Stefan's back. Stefan tells him to get Elena out of there and reveals he won't leave until Klaus is dead. Bonnie continues to cast the spell and as Klaus is weakened, Elijah approaches him. He starts to kill him, but Klaus croaks that he did not bury the family at sea - the bodies are safe. He promises to take Elijah to them if he saves him. Bonnie threatens to kill them both if Elijah doesn't slay Klaus, adding that she doesn't care if she dies. However, Elijah apologizes and dashes away with Klaus before Bonnie could stop them.

Meanwhile, Jeremy asks John if he read everything about the spell and knows what happened to the mother after the child was brought back to life. John admits that he does and adds that he has saved his daughter and found peace. He hands Jeremy a letter and his ring, asking him to give them to Elena. Alaric is unsure what is going on but hears Damon and Elena return. Damon puts Elena on a couch and tells her that if she comes back as a vampire he'll stake her himself. "So don't, because I can't stand the idea of you hating me forever," he adds. Alaric and Jeremy appear and ask about Elena. Damon is forced to tell them both that Jenna was killed. As they gather, John quietly leaves the house. Elena wakes up and admits that she feels fine. Outside, John collapses on the ground, dead.

Later, Elena gets ready for John and Jenna's funeral. Jeremy arrives and hands her John's letter and ring. Elena apologizes to him that he has lost so many people, but Jeremy tells Elena that he still has her. They hug sadly and Jeremy leave]s. Elena sits down and reads John's letter, which says: "It's no easy task being an ordinary parent to an extraordinary child. I failed in that task and because of my prejudice I failed you. I'm haunted by how things might have worked out differently if I'd been more willing to hear your side of things. For me, it's the end. For you, a chance to grow old and some day do better with your own child than I did with mine. It's for that child that I give you my ring.

I don't ask for your forgiveness or for you to forget. I ask only that you believe this. Whether you are reading this as a human or as a vampire I love you all the same, as I've always loved you and always will." At the funeral, Elena lays roses on the tombs of her family members.

Afterwards, Damon is reluctant to return for the wake but Stefan reminds him that Elena needs them. Damon asks what the plan is - how do they kill "an all powerful wolf-vamp and his two-face older brother?" Stefan admits that he has no idea but says he will not let Elena lose anyone else. Damon tells him not to make any promises and reveals that he has a werewolf bite. He adds that there is no cure but Stefan, who is devastated, promises that he will find a way. Damon asks him to keep this from Elena, adding that she does not need to mourn anyone else. The episode ends as he walks through the cemetery, with Stefan watching on in shock.