The story involves various enemies from the show’s history (Crab people, Underpants Gnomes, Gingers) attacking South Park and plunging the town into chaos. The boys try to reverse what damage has been done but must seek help, so Cartman suggests the New Kid (controlled by the player). The New Kid has just moved to South Park, so the other children are wary of the newcomer. Throughout the game, the New Kid will gain the trust of various characters and secure their help for the rest of the adventure.
Your main goal is to fight for ”the stick,” but what this stick does or why it is so important has not been stated at this point in time.