Set in German-occupied Norway, resistance fighter Knut Straud enlists the reluctant physicist Rolf Pedersen in an effort to destroy the German heavy water production plant in rural Telemark.
Dr. Rolf Pedersen
Kirk Douglas
Knut Straud
Richard Harris
Anna Pedersen
Ulla Jacobsson
Uncle
Michael Redgrave
Arne
David Weston
Major Frick
Anton Diffring
Terboven
Eric Porter
Col. Wilkinson
Mervyn Johns
Sigrid
Jennifer Hilary
Jensen
Roy Dotrice
Professor Logan
Barry Jones
Nilssen
Ralph Michael
General Bolt
Geoffrey Keen
Doctor
Maurice Denham
Knippelberg
Wolf Frees
General Courts
Robert Ayres
Gunnar
Sebastian Breaks
Freddy
John Golightly
Oli
Alan Howard
Henrik
Patrick Jordan
Claus
William Marlowe
Einar
Brook Williams
Captain of "Galtesund"
David Davies
Hartmuller
Karl Stepanek
Woman on Bus
Faith Brook
Mrs. Sandersen
Elvi Hale
Erhardt
Gerard Heinz
German Sergeant
Victor Beaumont
Businessman
Philo Hauser
Sturmfuhrer
George Murcell
Mr. Sandersen
Russell Waters
Watchman in Factory
Jan Conrad
Girl Student (uncredited)
Annette Andre