"The Wacky Molestation Adventure" is the sixteenth episode of Season Four, and the 64th overall episode of South Park. It aired on December 13, 2000.
To get back at his parents for not letting him go to a concert, Kyle tells the police that his parents molested him. Soon, all the kids catch on and do the same. The whole town is free of adults and divided into two rival cities. A couple's car breaks down in one of the cities and they are exposed to some very strange changes.
Cartman has four tickets to the "Raging Pussies" concert and the boys all want to go. When Kyle asks his parents for permission they characteristically forbid him from going. After negotiating relentlessly with them, Kyle's mom sarcastically agrees that Kyle can go if he cleans out the garage, shovels all the snow from the driveway and brings democracy to Cuba, all of which Kyle manages to achieve. Despite his success, his parents still refuse to let him go. In his fury, he questions his parents' authority and angrily wishes that he had no parents at all.
When Kyle shares his frustration with his friends, Cartman suggests that he call the police and claim that his parents have been "molestering" him, which will make them go away (a trick he played on his mother's ex-boyfriend). After some practice to get the accusation right, Kyle makes the call and the police arrest his parents. The boys then go to the concert and Kyle later hosts a party at his parent-free home and dances in his underwear. Seeing how liberated they are without parents, all of the children begin calling the police on their parents and teachers resulting in the adults being taken to prison. Even Shelly, Stan's sister, is arrested after she starts to attack Stan as he celebrates their parents' arrest. Before long, only the children populate the town, which is a slight parody of the 1984 horror film Children of the Corn.
Meanwhile, a couple from out of town, Mark and Linda Cotner, are having car trouble as they approach the limits of "Smiley Town" (the South Park sign has been overwritten with "Smiley Town"). They make it to a garage where they meet Butters and Craig. They ask for the nearest phone and are told that it is in "Treasure Cove". They also discover that South Park has been divided into "Smiley Town" and "Treasure Cove" by a long white line. Mark and Linda attempt to enter "Treasure Cove" but are attacked and driven back into Smiley Town. Craig and others come to their rescue and take them to meet the mayor of "Smiley Town" a.k.a, Cartman. Knowing that a ritual called "Carousel" is going to be held that night, Cartman asks Mark and Linda to go to Treasure Cove and retrieve a book for him. Getting the book will force a member of Treasure Cove to be sacrificed to The Provider. Mark and Linda agree to help, find the book, are attacked by residents of Treasure Cove, and taken back to the elementary school where Stan and Kyle are in charge.
Stan asks why Mark and Linda are helping the "fat ass" and offers to get them to the nearest phone if Mark and Linda agrees to help them instead. He then tells them the story of "the before time", which includes the reasons for the existence of Smiley Town, Treasure Cove, "Carousel", "The Provider" (who turns out to be a statue of John Elway), and "The M Word". Mark and Linda then agree to get the book from Smiley Town. Meanwhile, their parents are in prison working out their "sick sexual urges" with a counselor who helps them identify alternative activities to molesting their children.
Back in South Park, Mark gets Smiley Town's book for Stan and Mayor Cartman chooses Butters to be sacrificed. Realizing the danger to Butters, Mark and Linda attempt to interfere with the ceremony. In response, Cartman threatens to call the police and claim that the couple "molestered" the children. Mark realizes that the town has descended into anarchy because the parents were all falsely accused of molesting the children. He explains to the kids in a speech that their parents, the "birth givers", are their providers. The word "parents" resonates with the children and causes them to begin to remember. It turns out it has only been ten days since the town's parents and adults left. They allow Mark to make his important phone call and to also call to the police, clearing their parents of all wrongdoing. Mark tells Linda that maybe they should have children, but after all they have been through, she decides to get her tubes tied.
As the children await the return of their parents, and Mark and Linda drive up and reveal that Mark got the job that his "important call" was for: The manager of a Denny's restaurant in Breckenridge. When the parents arrive they now believe they are "cured" of the "sick sexual urges" that they never had (even though they now believe they actually had molested their kids). The parents are reunited with their children and Cartman, Stan, and Kyle (and Kenny's parents look all over for Kenny who was sacrificed), are confused by their parents' actions. Ultimately, to Mark and Linda's horror, the boys decide that they do not care about their parent's odd behavior since the problem had seemed to resolve itself.