I've thought about becoming a vampire, of course I've thought about it. If I did, there wouldn't be a Merge, and my skin would stay flawless forever. But I also wouldn't be able to have kids. I couldn't grow old with someone. And I don't even know if those are things that I want. But that's the point, I don't know yet. I can't make this decision until I'm sure.
— Lizzie to Sebastian
Kai Parker Screwed Us is the twelfth episode of the second season of Legacies and the twenty-eighth episode of the series overall.
CHRIS WOOD RETURNS AS THE VILLAINOUS KAI PARKER — When a series of events leads Josie, Lizzie and Alaric to the prison world, they come face to face with the twins' evil uncle Kai.
In a flashback to ten years prior, Dorian and Alaric stumble across bodies that have been fed on, and then burned to hide the evidence. Dorian suggests that it may not be Salvatore Students, however Alaric finds a Salvatore School badge on one of the bodies.
In the 2018 Prison World, Lizzie is furious with Alaric over the treatment of Sebastian; Sebastian reveals that he had help, and Josie realizes that this is why Emma Tig returned to the school. Sebastian is angry when Alaric suggests gathering weapons, and he and Sebastian get into a fight, ending in Alaric stabbing Sebastian in the stomach. Josie questions why they're rushing to leave, given Kai is desiccated, however Alaric reveals that he may not be desiccated, but refuses to reveal the situation regarding the Prison World and the children sent there. Alaric tells Josie to retrieve the mora miserium and return to the Salvatore Boarding House. Meanwhile, Sebastian attempts to convince Lizzie to explore the Prison World with him, just for one day. Despite her initial reluctance, she eventually agrees when Sebastian tells her that nobody else is present in the Prison World.
Alaric visits the bar where Bonnie Bennett had trapped Kai previously. He finds the bar desolate, but finds a note titled "To Whom It May Concern"; when he picks up the note, a video clip of Kai singing "All By Myself" begins playing on the TV.
Josie returns to the Boarding House looking for Lizzie and Sebastian, however she finds the place is empty, except for a girl, who she calls Jade. A flashback to ten years ago reveals the meeting between Josie and Jade, who is locked in the hall with Wendy and Diego via a boundary spell. Jade and Wendy are able to convince Josie to siphon the magic from the room so that they may go to their "party". Back in the 2018 Prison World, Jade tries to feed on Josie, but is stopped by Kai, who stabs her through the stomach, enticing Josie to leave with him if she wants to live.
Josie manages to get to safety with Kai, finally realizing who he is, he explains that the girl that tried to kill her — and the other children — run the place. He explains that they hunt him down each day, kill him, and he resurrects given he is immortal and tied to the Prison World. He questions why Josie is in the Prison World, and she explains the situation regarding the mora miserium and its degradation, and being tricked by Alyssa.
Back in the bar, Alaric watches the tape Kai left. On the tape, Kai thanks Alaric for sending the children to the Prison World, given the first thing they did when they were bored was wake him up. Kai questions why Alaric would be dumb enough to come to the Prison World, but Alaric shoots the TV before the tape can play any further. He is attacked by Diego, who throws him across the bar before activating his werewolf features including his face and claws. He reveals that he is able to control it, given he has had 10 years of the same full moon and thousands of turns. Diego is ready to attack Alaric, however is killed by Kai who rips out his heart; Alaric kills him with an arrow shortly before Josie arrives.
Sebastian shows Lizzie a large mansion, telling her that it is her and handing her the keys. The two change into formal wear and dance together in the parlor.
Kai awakens, exclaiming that the first death is free, but it will be harder next time. Kai is surprised when he stands, however to find Josie has chained Alaric to the chair, much like Bonnie tied Kai to the chair previously. Josie reveals that she is getting everyone out of the Prison World, even if it means working with her uncle.
Kai tells Josie everything that she needs: a celestial event, the ascendant and Bennett Blood to escape. Tensions arise when Josie reveals that she didn’t bring any blood to the Prison World given that it wasn't a planned visit. Josie questions if a mora miserium is powerful enough to power the spell without a celestial event, and Kai questions where it is. Josie reveals that it is in the clearing, but cloaked, and Kai reminisces on when Bonnie performed the same trick on her toy bear. As a show of good faith, Kai gives Josie the ascendant, and she reveals she is in possession of the sand clock.
Meanwhile, Lizzie and Sebastian enjoy their fantasy, dancing in the mansion. Lizzie tells Sebastian that she doesn't want the day to end, and Sebastian suggests that the day doesn't have to end. Lizzie suggests that they can convince Alaric that he was wrong and to take Sebastian back, however he reveals that he doesn’t want to return, but to remain in the Prison World forever.
At Mystic Falls Hospital, Kai questions Josie about Malivore, and she reveals the details surrounding it. Josie questions what they’re doing at the hospital, and Kai reveals that during his time in the Prison World, he discovered someone by the name of "Smithfield" donating blood, but on deeper inspection, her maiden name is Bennett. He finds Jade has drank all of the blood, however, and she tries to attack the two, but Kai is able to lock her in the blood storage room with a spell.
Diego awakens in the bar and is ready to attack Alaric, before he is interrupted by Wendy. She tells Alaric that it is time for his trial, similar to the trial they were given before they were banished.
Back at the hospital, Josie tells Kai that she needs to return to the bar to save Alaric before Diego awakens. Kai tells her that it is no use without Bennett blood, and Josie reveals a vial of blood in her pocket, revealing that it is left over from when they sent the sand clock to the Prison World. Kai is attacked by Jade, but it is eventually revealed that the two are working together. Josie tries to flee, but Kai immobilizes her with a spell, revealing that she was right not to trust him; he takes the blood from her. Kai reveals that he in fact is the leader of the Prison World, not Jade. He tells Jade to take Josie to Alaric, but not to kill her yet, but to allow the two to suffer. With this, he kisses her forehead and leaves.
Sebastian and Lizzie talk, and Sebastian tells her that he likes how peaceful the world is, given his enhanced hearing and the noises in the modern world. Lizzie again recites that she cannot stay, however Sebastian tries to convince her that they could go anywhere and be anyone, including kings and queens. Lizzie tells him that she has family, and could not deal with Sebastian not aging, whilst she grows old. Sebastian tells her that he has a solution for the issue, and asks her if he can turn her into a vampire.
Back at the bar, Alaric tells Wendy that he can handle the torture, so there is no point. Jade enters shortly after telling him that he perhaps cannot handle seeing his daughter be tortured. Jade demands an explanation from Alaric, telling him that she waited ten years. In a flashback, Alaric questions Jade over what happened with the bodies, however Jade is reluctant to answer. Jade tells Alaric that she wasn't there when the people were killed, however Alaric hands her the badge, telling her that the badge is hers and she was wearing it when she died. Jade leaves, telling Alaric to punish them already as he has already decided they're guilty. Back in the 2018 Prison World, Alaric tells them that he had no other choice but to send them away, given they were a danger to the world; he reveals that he made a mistake and should've killed them instead. He further reveals that Caroline was the one who convinced him to show them mercy. Jade dismisses the others, asking them to check on Kai, ensuring he doesn't leave them behind.
Jade tells Alaric that he isn't right, and will tell him exactly what happened that night. She reveals that Inez invited her to a party, and Wendy and came too. Jade realized that the party was a competition to see who could invite the biggest "freak", and within one glance they knew they were different. Jade suggests leaving, however one of the guys throws a rugby ball at Diego, causing a fight in which Diego rips on the guys arm. Jade found out that night that she is a Ripper, and she killed Inez. Despite this, Jade felt remorse and guilt, turning her humanity off that night. Jade allows Alaric to stand, telling him that she wants to play a game.
Back at the mansion, Sebastian questions if Lizzie has decided whilst they enjoy a glass of wine. She reveals that she has thought about becoming a vampire and the implications this would have on fixing the Merge. Despite this, she doesn't feel ready to trade off the decision to start a family or have children. Sebastian tells her that he was afraid she would say that, and that his offer isn't a choice; it is revealed that he laced her wine with blood. Fearful of Sebastian and his options, Lizzie runs, but is caught by Sebastian, who explains how he will not lose someone like he did Cassandra. He accidentally calls Lizzie "Cassandra", which startles her. The two kiss and Lizzie begins siphoning the magic from Sebastian, causing him to desiccate; she remarks that she thinks they should see other people.
Jade brings Alaric to the Woods, telling him that they're going to play hide and seek. Alaric initially refuses, however Jade threatens him with harming Josie. She reveals that if he can survive 24 hours, she will allow Josie to live.
Wendy and Diego arrive at the Old Mill to find letters from Kai, and Wendy realizes that Kai screwed them over. At the docks, Kai attempts to activate the ascendant by pouring on the blood. He is dumbfounded when the blood doesn't work, however and begins siphoning the magic from it to reveal the blood is actually a miniature bottle of vodka cloaked with an illusion.
Josie escapes from restraints of the bar to find the phone ringing. She answers to find Kai on the other side, who tells her that he is proud of her for the deception. She reveals that she won't help him leave the Prison World, but he reveals that there is another way to leave the Prison World. He tells her to break the sand clock, as she will need all of the power to escape. He reveals that he found his own way out of the Prison World, but when Josie asks he is reluctant to tell. He reveals that Josette thought she was smarter than him too and was punished, and to use the sand clock, Josie must become something dark and evil, but will be able to make her own door out of the Prison World. Kai tells her she won't remember anything, as she won't remember him, and Josie finally realizes that he is at the Malivore pit. She warns him not to jump, as he will be trapped and alone for eternity, however he reveals that this is normal for him. Just as Kai jumps into the portal she smashes the sand clock, absorbing all of the dark magic. This affects Lizzie, who blacks out at the wheel of the car she is using to transport Sebastian, and the car crashes.
Jade tells Diego and Wendy that she doesn't really care about Kai screwing them over, but only cares about finding Alaric. She asks Wendy to do a locator spell, who remarks that it isn’t good sport to cheat; nevertheless, Wendy performs the locator spell. It is revealed that Alaric is beneath the tunnels in the Armory, and Jade remarks that it'll be a good challenge.
Kai is seen emerging from the other end of the Malivore portal in Mystic Falls, 2028. The Necromancer questions who he is, and Kai remarks that he doesn’t know the half of it.
Jade, Wendy and Diego are bound to the Prison World just like Kai; this means they cannot age, nor be permanently killed.
After ten years, and thousands of turns, in the 2018 Prison World on the night of the full moon, Diego learns to control his transformation. However, his form is beyond that of a wolf and is more like a man-beast hybrid.
Sebastian wants to stay in the prison world and wants to turn Lizzie into a vampire against her will. He places his blood into the wine she drank.
Lizzie reveals she's thought about being turned into a vampire as a way to stop the Merge but also realizes she wouldn't be able to have children or grow old with someone. She tells Sebastian she doesn't know what she wants at the moment.
Kai and Jade were involved in a physical relationship, even though she admits she prefers girls and doesn't seemed to be bothered that Kai screwed them over.
Jade learns that she is a Ripper, losing control towards blood, and killed her friend Inez. This event and her actions are partially responsible for why she, Wendy and Diego were banished to the prison world.
Kai Parker escapes the 2018 prison world by using the Malivore pit, a portal to another dimension. After emerging from the pit in the real world, he meets the Necromancer.
This is the first episode where no actual mythological monster appears.
This episode contains dramatic irony. The audience is aware that Sebastian is lying when he tells Lizzie that there is nobody else in the Prison World, however Lizzie is not aware and must accept what Sebastian tells her as the truth.