At the foot of the advancing glacier which heralds a new ice age, Fisher Highsmith struggles with an impossible task. Why - how - have various objects - bricks, stones, a ray-gun, dead fish and the charred corpses of sixteen stone-age men apparently fallen out of the sky? The next two bodies give the clue. One is still alive - and he's angry. The other is a woman. She's been mauled, bludgeoned, boiled and eaten to death - but what's left bears witness to humanity's incredible future.