to compose the film's score, as they were good friends and regular collaborators. Zimmer felt that the score was a "unique challenge", and he had to "try and express the style of The Simpsons without wearing the audience out". He used Danny Elfman's original opening theme, but did not wish to overuse it. He created themes for each member of the family. Homer's leitmotif was a major focus, and Zimmer also composed smaller themes for Bart and Marge. Regular television series composer Alf Clausen was not asked to score the film, noting: "sometimes you're the windshield, sometimes you're the bug". In addition to their appearance in the film, Green Day recorded its own version of the Simpsons theme, and released it as a single. Zimmer turned the Spider-Pig song into a choral piece, which was a joke he never intended to be put into the film. Zimmer also had to write foreign-language lyrics for the 32 dubbed versions of the song when the film was released internationally. He found translating the song into Spanish the hardest to write. The same choir learned to sing the piece for each of the foreign-language dubs. Themes Al Jean described the film's message as being "a man should listen to his wife". In addition, the film parodies two major contemporary issues, religion and environmentalism. The theme of environmentalism is present throughout the film: in Homer's polluting of Lake Springfield, Green Day's cameo, Lisa's activism and her romance with Colin. The villainous Russ Cargill is head of the Environmental Protection Agency. Reviewer Ed Gonzalez argued the plot was a satire of the government's reaction to the effects of Hurricane Katrina on New Orleans. Ian Nathan of Empire magazine criticized this focus, believing it gave the film an "overt political agenda [which] border[s] on polemic". James D. Bloom of Muhlenberg College commented on the "explicitness" of the film's "intellectual agenda", on this issue, shown particularly through Lisa. He wrote that the film's first post-opening credits scene, which sees Green Day fail in an attempt to engage their audience on the issue of the environment, "sets in motion a plot expressly built around cultural agenda-setting" and "reflection on timely 'issues'." Religion is focused on in Grampa's momentary possession, and Marge believing what he said to be a message from God. Groening joked the film "posit[s] the existence of a very active God", when asked if he believed