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.
John Mills
Commandant Fraser
John Gregson
Lieutenant Alec Duffy
Donald Sinden
Lieutenant Tom Corbett
James Robertson Justice
Admiral Ryder
Michael Medwin
Smart
Theodore Bikel
German Officer
James Kenney
Abercrombie
William Russell
Ramsey
