A story of greatness through severe trial and hope; of betrayal when hope is fulfilled - the interaction of twin planets , and the power of destiny prevailing still in the unknowable depths of the human psyche after fourteen hundred years from Earth. The story deals with twin planets. First Planet is toxic. A million people are housed there, comfortably, under a technologically perfect hemispheric Dome. They are quite brilliant but their lives are short. Immortals, living on Sister World, a paradise, provide for and reward them for their creativity in art and scientific inventions, treating them as a brain farm. After four hundred years two men escape from the Dome. They discover their origins by use of a marvelous instrument, a Vade Mecum, which belongs to Immortals and is illegal in their possession. The planet kills the men, but the Vade Mecum, by the numinous quality of its sensors, returns to the Dome with its recorded information. The daughter of one of the men writes a history from its revelation which challenges the Immortals to a crisis of decision they would do anything to avoid. The catalyst of all this is the Immortal Seneschal, lone mediator of the peoples. He lives alone on First Planet in a beautiful Glass City, and oversees all providence for the Dome, which is carried out by robots. His senses are omnipresent, and he is aware of all vicissitudes of the Vade Mecum, but reveals nothing to his people on Sister World. He has a purpose of his own, unsuspected by either peoples, and reveals his abilities to no one - not even the woman he loves, the great Lifespanner musician, Felice, who leaves him because he will not grant her the prime award of immortality she so well deserves; nor does he explain himself. But their love is great and has its own effect. The result of this is irruption on both planets.