The naturalist seeks out the giant saggy-skinned frog of Lake Titicaca in South America. He begins his research at London's Natural History Museum, hoping to find the amphibian whose natural habitat is two miles up in the Bolivian Andes. The team follows in the footsteps of Jacques Cousteau, who visited the area in the early 1960s. However, finding the creature proves a mammoth task as altitude sickness slows the group down