The three are Claire, aged thirty-three, born in Battersea, writer of spicy novels;Sir John, head of a armament combine;Keith, an American, president of the league of Militaristic Pacifists. When the air-ship on which they are traveling breaks in half after a submarine earthquake, they find themselves on a beach near basalt mountains, intensely cold, Clair and Keith in pajamas, Sir John in evening clothes. Gradually in their wandering south, it is revealed to them that they have gone back twenty-five thousand years, that they are on the lost continent Atlantis, that the great beasts they glimpse are mammoths and sabre-toothed tigers, that the Cro-Magnards who take them in are not savages but clean and kindly children, whose unspoiled ways are worth adoption. The Cro-Magnards live in painted caves, wear no clothing, know the uses of fire but possess no vessels, are blissfully ignorant of agriculture. At the annual mating, lovers choose each other for the winter.
