It is 1964 and a nucleur war has managed to obliterate the entire human population of the Northern Hemisphere. However an American submmarine has managed to survive and has found a temporary safe haven in Australia. Here there is a growing despair after this nucleur incident yet this seems to be covered by a life-as-usual effort.
Captain Dwight Towers (Gregory Peck) was on this submarine and is in denial over the loss of his wife and children in the holocaust. However he soon meets the beautiful, yet burdened, Moira Davidson (Ava Gardner) and the two begin to fall in love.