Fired with a determination to find the reason why the Moon affects his planet so badly, Berannes gains the magical skills to transport himself there. On misty, sparsely-populated Lume he discovers the sorcerer Tironsar, bent on completing his mysterious Lodestone, which may give him supreme domination over many worlds; and the lovely princess Falmorwy of the Far Galaxy, who is somehow involved in the sorcerer's plan.

Berannes finds his dreams of becoming a hero don't always turn out the right way. The two "star-horses" may be allies, but they carelessly order him around; and dwarfish Dron and Lalmi also have a different agenda for him. Even his growing love for the princess brings him inner torment, as she insists on returning to the perils of the sorcerer's Citadel on a quest for further information. And always he is conscious of the fact that time is running out—fast!