 The boys get recruited to join a choir group performing in Costa Rica to help save the rainforest. The choir leader, Miss Stevens, wants to teach everyone how wonder the rainforest is, and leads the group on a nature tour, only to get hopelessly lost in the wilderness where they fall victim to wild animals, quicksand, violent natives and rebel troops. Only Cartman, who sneaks away after getting fed up with Miss Stevens  love of nature, can save his classmates.