"The Ungroundable" is the fourteenth and final episode of Season Twelve, and the 181st overall episode of South Park. It aired on November 19, 2008.
Butters is sure he’s seen a Vampire at school but he can’t get anyone to listen to him. Tired of being teased at school and punished by his parents, Butters joins the Vampire group and becomes "ungroundable." Meanwhile, the Goth Kids are angry and frustrated when the other kids can’t tell the difference between a Goth and a Vampire.
The fourth graders are in a computer class being taught by Mr. Mackey, but no one is paying attention (all of them are playing Call of Duty: World at War). Butters runs into the classroom claiming that he's seen vampires all around the school. None of the other kids believe him and Cartman suggests that he go "document the vampires' movements" (simply to get rid of him).
The members of the South Park Vampire Society are sitting in the gym, discussing what type of vampire they are. Butters spies on them, documenting their activities in his tape recorder. One of the vampires suggests that they "feed", and they begin to drink Clammato (a mixture of clam and tomato juice usually served with certain cocktails). Butters' tape recorder malfunctions, and it begins to blare out another of Butters' recordings. The vampire kids suddenly appear, and Butters (believing they are real vampires but doesn't understand, as he seem to be gullible) pulls out a crucifix (a common way to repel or keep away a vampire other than a wooden stake), attempting to repel them before running away.
The Goth Kids see the vampires and are horrified, wondering if they're trying to be goth. One of them tells the others that they're "vamp", and that they "wear plastic fangs and drink freakin' Clammato juice". They confront the vampire kids, who tell them that they're just as dark as the goth kids, maybe even darker. The goth kids, meanwhile, point out that the vamps don't even smoke.
After a minor confrontation with his parents, Butters thinks aloud to himself that nobody listens to him, and that vampires probably don't get "hollered at" (yelled at or confronted in a way) by their parents. The next day, Butters approaches the vampire kids, telling them that he wants to be a vampire. The vamp kids attempt to take over the spaces used by the goth kids who tell them to go away. As part of the initiation process, the vampire kids then take Butters to the South Park Mall, where they go to Hot Topic and buy Butters black clothing, hair dye, jewelry and plastic vampire teeth. They then make him drink Clammato juice to complete his "transformation".
Butters returns home to his parents, who are angry at him because of his lateness and his dyed hair. Butters responds that because he is a vampire, he is no longer subject to the rules of humans, stating that he is "ungroundable".
Butters sneaks into Cartman's room in the middle of the night attempting to feed off him (clearly saying if someone has to die so he can live then he chooses Cartman), failing to go through with biting him. When asked by his mother what happened Cartman responds, "Well Mom, apparently Butters is gay, finds me very attractive, and confused about his sexual identity, puked up all over my floor."
The goth kids kidnap the head 'vampire' and successfully threaten him into admitting he is not really a vampire. Afterwards, they decide to mail him to one place that he would be miserable and tormented: Scottsdale.
At home, Butters' parents explain that they got a call from Liane Cartman and ask him if he "got gay with one of his schoolmates tonight", to which Butters responds that he needs to eat and leaves out of his window. His parents comment that Butters has "become something we cannot ground".
Butters convinces the goth kids to burn down the local 'Hot Topic' store. At home, he is normal again and groundable, after his parents punish him over incorrectly organizing the pantry. The goth kids hold an assembly to list/make people realize they are different from the vampire wannabes. They then flip the audience off and say "fuck all of you" which makes the crowd cheer even louder.