educational video shown to Cartman is based on Monty Python alum John Cleese's Hitler impression, which both Parker and Stone particularly praised. Actress and singer Tina Yothers, best known for her role in the television series Family Ties, is featured in the episode as a celebrity judge in the school's costume judging contest. About one year after the episode aired, Stone met Yothers at a venue where she was performing with her band. Stone was uncomfortable because it was the first time he had met a celebrity the show previously mocked, but Yothers said she was a big fan of the show and enjoyed her parody appearance. She used a clip of Kyle saying "Up yours, Tina Yothers" from the episode as an introductory sound clip to introduce her band's shows. Kenny is turned into a zombie after a mortician accidentally knocks Worcestershire sauce, a fermented liquid condiment, into his embalming fluid. Parker and Stone originally planned to have a Dr Pepper fall into the embalming fluid (in a belated response to that product's slogan "Dr Pepper, What's the Worst That Could Happen?"), but it was changed after the soft drink company objected to that use of their product. The episode features a reference to Home Improvement season 2 episode 6 “The Haunting of Taylor House”. Stan and Wendy were supposed to dress up as Raggedy Anne and Raggedy Andy but Wendy didn’t dress up as Raggedy Anne, similar to Brad and Jennifer on the episode. The episode features a parody of the Michael Jackson song "Thriller", as well as the music video. When Chef becomes a zombie, he is dressed like Jackson from the "Thriller" video, and he and the other zombies dance in a similar way. Chef also shouts "Oh" the same way Jackson often did during music performances. The song Chef sings is also similar to the actual "Thriller" song, but Parker said they deliberately made it "(just) different enough that we can't get sued". Stan is ridiculed for his likeness to Raggedy Andy, based on the rag doll character by children's writer Johnny Gruelle; Stan's girlfriend Wendy was originally supposed to dress as Raggedy Ann with Stan, but she instead chose to dress as Chewbacca. When Cartman later dons a "ghost" costume, it resembles a costume from the Ku Klux Klan, the militant white supremacy organization. Parker and Stone said they feel Klan jokes are particularly