Tom Jericho
Hester Wallace
Claire Romilly
Mr. Wigram
Puck
Logie
Leveret
Cave
Baxter
Pinker
Kingcome
Upjohn
Skynner
Admiral Trowbridge
Villiers
Commander Hammerbeck
Mr. Mermagen
Heaviside
Kay
U-boat Commander
The story of the WWII project to crack the code behind the Enigma machine, used by the Germans to encrypt messages sent to their submarines.