Now the surface was a lethal desert of slag and rolling clouds. Endless clouds drifted back and forth, blotting out the red Sun. Occasionally something metallic stirred, moving through the remains of a city, threading its way across the tortured terrain of the countryside. A leady, a surface robot, immune to radiation, constructed with feverish haste in the last months before the cold war became literally hot.

Leadys, crawling along the ground, moving over the oceans or through the skies in slender, blackened craft, creatures that could exist where no life could remain, metal and plastic figures that waged a war Man had conceived, but which he could not fight himself. Human beings had invented war, invented and manufactured the weapons, even invented the players, the fighters, the actors of the war. But they themselves could not venture forth, could not wage it themselves. In all the world—in Russia, in Europe, America, Africa—no living human being remained. They were under the surface, in the deep shelters that had been carefully planned and built, even as the first bombs began to fall.

It was a brilliant idea and the only idea that could have worked. Up above, on the ruined, blasted surface of what had once been a living planet, the leady crawled and scurried, and fought Man's war. And undersurface, in the depths of the planet, human beings toiled endlessly to produce the weapons to continue the fight, month by month, year by year.