Science fiction has its immortals - authors whose impact was so tremendous that they belong in a class by themselves. Olaf Stapledon extended the boundaries of science fiction to the infinite, and there are few of the major authors who do not directly or indirectly owe him a great debt.

This volume of his short science fiction and fantasy includes in addition to the five stories, an uncollected radio script from which this volume takes its title and an uncollected 1948 address to the British Interplanetary Society.