Premise: "Treehouse of Horror XI" is the first episode of "The Simpsons"<nowiki>'</nowiki> twelfth season and the 249th overall, and the eleventh Halloween episode. The episode features "G-G-Ghost D-D-Dad", "Scary Tales Can Come True" and "Night of the Dolphin" and was written by Rob LaZebnik (story by Mike Scully), John Frink and Don Payne and Carolyn Omine and directed by Matthew Nastuk.
Hypothesis: The 11th Halloween episode of the Simpsons was played in the 12th season.