In common with all previous "Treehouse of Horror" episodes, the program is made up of three self-contained stories; "The Diving Bell and the Butterball", "Dial 'D" for Diddly" and "In the Na'Vi". The first story is a parody of the 2007 French movie The Diving Bell and the Butterfly. In the second story, which references the TV series Dexter, the Simpsons' pious Christian neighbor becomes a serial killer. The final story is a parody of the 2009 science fiction movie Avatar. The opening sequence spoofs the 2010 biographical film 127 Hours.