
In World War II, the greatest threat to the British navy is the German battleship Tirpitz. While anchored in a Norwegian fjord, it is impossible to attack by conventional means, so a plan is hatched for a special commando unit to attack it, using midget submarines to plant underwater explosives.

as Commandant Fraser

as Lieutenant Alec Duffy

as Lieutenant Tom Corbett

as Admiral Ryder

as Smart

as German Officer

as Abercrombie

as Ramsey

as Captain of the Tirpitz

as Cox

as McCleery

as CPO Chubb

as George

as Winley

as Diver Navigator, X2

as Hutchins

as Engineer, X2

as Lt. Anderson

as No. 1, X2

as Officer Interpreter

as Officer on Towing Sub. (1)

as Officer on Towing Sub. (2)

as German Officer on Tirpitz

as RAF Officer (uncredited)

as German Navy Officer (uncredited)

as Sailor on Towing Sub (uncredited)

as Naval Officer in Briefing Room (uncredited)