David travels to Papua New Guinea in search of humpback whales. He manages to dive American B17 bomber wrecks, virgin coral reefs and even explores head hunter caves and volcanoes, but all his diving, fails to locate the whales. David then travels to the islands of Tonga and after weeks of trying, he eventually locates male humpbacks fighting for the rights to mate with a female. The underwater footage David and his crew gain during the males aggressive behaviour is both dangerous and spectacular. Eventually David manages to find a female humpback whale with a one day old baby at her side. The scenes of David swimming with the new born whale represent some of the finest underwater footage ever recorded. 50 minute duration. Rated (G)