A billion years in the future there was a city standing on a plain where grass grew that was blue and glassy and tinkled with a high crystalline chiming as the wind blew through it. But the city had never been built by humans, and it warned him away with a voice he could not disobey.

Then the sea came, and for a long time thereafter he was trapped within a mountain; he had to drive onward till it had eroded back to the ground.

The sun grew hotter and whiter as the hydrogen-helium cycle increased its intensity. Earth spiraled slowly closer to it, the friction of gas and dust clouds in space taking their infinitesimal toll of its energy over billions of years.

How many intelligent races had risen on Earth and had their day, and died, since the age when man first came out of the jungle? At least, he thought tiredly, we were the first.

A hundred billion years in the future, the sun had used up its last reserves of nuclear reactions. Saunders looked out on a bare mountain scene, grim as the Moon—but the Moon had long ago fallen back toward its parent world and exploded into a meteoric rain. Earth faced its primary now; its day was as long as its year. Saunders saw part of the sun’s huge blood-red disc shining wanly.

So good-bye, Sol, he thought. Good-bye, and thank you for many million years of warmth and light. Sleep well, old friend.

Some billions of years beyond, there was nothing but the elemental dark. Entropy had reached a maximum, the energy sources were used up, the universe was dead.

The universe was dead!

He screamed with the graveyard terror of it and flung the machine onward. Had it not been for the gods’ command, he might have let it hang there, might have opened the door to airlessness and absolute zero to die. But he had to go on. He had reached the end of all things, but he had to go on. Beyond the end of time—

Billions upon billions of years fled. Saunders lay in his machine, sunk into an apathetic coma. Once he roused himself to eat, feeling the sardonic humor of the situation—the last living creature, the last free energy in all the cindered cosmos, fixing a sandwich.

Many billions of years in the future, Saunders paused again. He looked out into blackness. But with a sudden shock he discerned a far faint glow, the vaguest imaginable blur of light out in the heavens.

Trembling, he jumped forward another billion years. The light was stronger now, a great sprawling radiance swirling inchoately in the sky.

The universe was re-forming.

It made sense, thought Saunders, fighting for self-control. Space had expanded to some kind of limit, now it was collapsing in on itself to start the cycle anew—the cycle that had been repeated none knew how many times in the past. The universe was mortal, but it was a phoenix which would never really die.