This documentary comprehensively traces the development of these ultimate weapons, from earliest beginnings, the greased-leather Drebbel boat of 1620, the egg-shaped Turtle of America's Revolutionary War, the famous Holland boats, the terrors and triumphs of submarine warfare in WWI and WWII, with boats both hunting and hunted, through to today's Leviathans. Using a vast archive of documentary footage, the program includes never before released film of both nuclear and conventional attack and hunter-killer submarines with full coverage of their weapons systems.