The success of this first full-scale nuclear power station on the shores of Lake Huron has shown the way for the economic large-scale production of electricity from uranium. This film describes the plant at Douglas Point, Ontario, and the process by which the uranium atom is split, employing heavy water with a special property, deuterium, giving the name CANDU (Canada Deuterium Uranium) to the Canadian system of atomic energy production. Produced for the NFB by Crawley Films Ltd. for Atomic Energy of Canada Limited.