The Real Heroes of Telemark also tells the true (as opposed to the movie, starring Kirk Douglas) story of this sabotage against the heavy water plant at Rjukan, destroying Hitler'shope of a nuclear bomb. Bravery, cunning and endurance over and beyond the call of duty on the part of the SOE (a forerunner of SAS) agents parachuted into Norway made this operation, which met with much problems, possible.
From http://www.janeriks.no/Books/Norway_WWII.htm
and
From http://intellit.muskingum.edu/wwii_folder/wwiieurope_folder/wwiieurresothern-z.htmlb. Norsk Hydro Raid
Allied efforts to interrupt heavy water production at the Norsk Hydro plant near Rjukan in German-occupied Norway included a failed glider assault by British commandos in November 1942, the destruction of a portion of the plant by an SOE team of Norwegians in February 1943, an Eighth Air Force bombing raid in November 1943 that left the plant largely intact, and a subsequent Norwegian Resistance operation in February 1944 that destroyed a final shipment of heavy water on its way to Germany.
The efforts against Norsk Hydro were loosely the basis for the 1965 movie "The Heroes of Telemark," starring Kirk Douglas and Richard Harris.