A brother and sister "Robert & Judy Maitland" are trying to turn some jungle acreage into a rubber plantation so hire a group of the natives to help out by "cutting down the trees so they can plant more trees". The couple - via the auspices of local commissioner Charles Irwin - try to convince our tousled hero "Bomba" (Johnny Sheffield) to help out; but he is determined to track down a man-eating ver mais...