A reconstruction of the two last sabotage actions against the Norsk Hydro Heavy Water (Deuterium, D2O) plant at Vemork, Rjukan, in 1943-44. After the first two allied attempt of stopping the production by British soldiers and American bombings, allied trained young local patriots became successful saboteurs. First by undermining the factory, and later after a rebuild, the sinking of the heavily guarded ferry trying to transport the heavy water to Germany, on Lake Tinnsjo.