The low budget precluded the use of stunt men or elaborate special effects. The cast and crew climbed up mountains, hacked through thick jungle, and rode ferocious Amazonian river rapids on rafts built by locals. At one point, a storm caused a river to flood, covering the film sets in several feet of water and destroying all the rafts built for the film. This flooding was immediately incorporated into the story, as a sequence including a flood and subsequent rebuilding of rafts was shot.