The boys are playing shuttlecraft Spontaneity in the new minivan that Cartman's mother has purchased. They go on an away mission and Cartman, as usual, gives Kyle a hard time about being a Jew, in this case a "Vulcan Jew." Cartman again tries to inform Kyle that in the movie The Passion of the Christ, the Jews are the devil; he's seen the movie 34 times and he knows that the Jews had plenty of opportunity to save Jesus, but didn't. Stan and Kenny are tired of hearing them argue about the film and they decide to leave. Cartman accuses Kyle of being scared to learn the truth about the Jews as they are evil, evil people. Kyle debates and then decides to go and see the movie for himself. He endures the film and its depiction of the final hours of Christ's life in a state of constant horror and disgust. When he leaves the theater, he wonders how the Jews could have done that to Jesus, feeling enormous amounts of guilt mainly due to his membership of the religion in question.
He goes to Cartman's house and sadly tells Cartman, "you were right," a statement that Cartman relishes. Cartman prays to a picture of Mel Gibson (in Braveheart) and promises to organize the masses and spread the word about The Passion. Stan and Kenny decide they need to see the film, but their feeling about the film is simply that it sucked and they want their money back. Stan calls it a "snuff film" and the guy at the box office tells them to go see the producer of the film if they want to get their money back; meanwhile Kyle is dreaming about killing Jesus which turns him into a nervous wreck. Stan and Kenny try to get in contact with Mel Gibson by calling a 1-800 number they have found on a website. Stan dials the number which brings him in contact with someone who is running "Mel Gibson's The Passion Fan Club," and they want to know how to contact Gibson and get their money back. The guy on the phone, whom Stan does not recognize as Cartman, isn't any help (as he insults Stan over his inability to appreciate the movie, then hangs up after Stan deduces its him) other than telling them that Mel Gibson lives in Malibu. Stan decides that he and Kenny need to go there, because it's no longer about getting their money back, it's about holding the filmmaker responsible, which Stan says is how they got their money back for BASEketball.
Cartman is dressing in a brown Adolf Hitler-esque uniform and getting ready for the meeting he is holding in his backyard. People have gathered in the yard to celebrate their rediscovery of their Christianity, but it is actually a club Cartman plans to use to follow in Hitler's footsteps and create a second Holocaust. Cartman suggests those in attendance each take one more person to see The Passion before they begin "the cleansing." Out in Malibu, Stan and Kenny make their way into Mel Gibson's mansion. They see the man himself, but Mel Gibson starts going crazy while telling them that he won't be giving them their ticket money back, as well as being an obvious masochist. Back in South Park, Kyle talks with Father Maxi about Jesus, and makes up a fictitious friend in order to ask him how he can deal with his own guilt. Father Maxi suggests "atonement" for Kyle's friend, which gives Kyle an idea. Stan and Kenny manage to steal the money they want from Gibson's wallet and escape from the lunatic Gibson. In a rally outside the theater where "The Passion" is being shown, Cartman begins speaking (poorly pronounced) German and his crowd of followers mistake his words for Aramaic, the language spoken in the film. He gets the crowd to march after him and as he exclaims 1. "Es Ist Zeit zu säubern" ("It´s time to clean") the crowd replies "Wir müssen die Juden ausrotten!" ("We must exterminate the Jews!") 2."Es ist Zeit für Rache!" ("It is time for revenge") the crowd replies" Wir müssen die Juden ausrotten!" ("We must exterminate the Jews!")
Kyle goes to his synagogue and suggests to the gathering that as the American government had for racial segregation and slavery, and the Germans had for the Holocaust, the Jewish community needs to apologize for the death of Jesus. Kyle's parents and the other Jews are outraged at the suggestion that they should apologize and are disturbed by the effect the movie is having on people, claiming it stereotypes Jews (ironically, every Jew in the temple has a big nose and speaks in a thick Yiddish accent). The rabbi suggests that "...we live in a rational society where people will realize it is just a movie." At that point, Cartman is seen outside the temple with his followers, goose-stepping down the street and chanting their German phrases. Meanwhile, on the bus back from Malibu, Stan and Kenny realize that Gibson is chasing after the bus, recreating the famous truck chase scene from Mad Max 2, also honking his horn and shouting "Qapla!" (in reference to Star Trek) to get his $18 back. The Jewish congregation marches on the theater and demands that the movie be removed from the theater, while Cartman and his group come from the other direction. Their dialogue about the film is interrupted by the arrival of Stan and Kenny's bus being chased by Gibson. Gibson's tanker truck explodes in front of the theater. Cartman sees this and rushes over to offer the services of his following, but Mel has gone completely off the deep end. Seeing Gibson's behavior makes Kyle wonder why he was freaked out by his movie. Gibson demands his money back only for Stan to refuse saying the movie sucked. Gibson counter's by saying "You can't say my movie sucks or you're saying Christianity sucks." Stan makes a speech about how while it is a good thing to want to be a better Christian you should follow the teachings of Jesus, not the way in which he died, stating also that focusing on his death was how people thought in the Dark Ages and hundreds of people were killed because of it. The townspeople realize that Stan is right and promise to stop following Cartman. In the end Gibson shows his insanity again by gleefully defecating into Cartman's face. Kyle realizes his mistake and returns to normal, having lost all respect for Mel Gibson.