Treehouse of Horror II is the seventh episode of The Simpsons third season, the second Simpsons Halloween episode, and the first Halloween episode where names in the closing credits were replaced by 'spooky name' parodies. The episode aired on October 31, 1991. In production order, this was the first episode to be animated by Anivision, which was the first non-AKOM overseas studio to work on the show.