He was born under a dark moon, Aljan, prince of the unicorns, high-spirited, impetuous. His constant questioning and recklessness are the despair of his mighty father, Korr. Reluctantly, Korr allows Jan to accompany the other initiate warriors on a pilgrimage to their lost ancestral home. There, they will view their destinies in the Mirror of the Moon, a rite of passage for all who wish to join the Circle of the Unicorns.

It is a perilous journey, with ever-present threats from deadly gryphons, sly pans, wyverns, pards, and renegade unicorns. Jan vows to behave. But his curiosity and impulsiveness lead him, along with his friend Dagg and their mentor, the female warrior Tek, into the greatest dangers. Miraculously, though, they are always rescued, and as they travel through the Pan Woods, across the Great Grass Plain, and finally to the sacred Hallow Hills, Jan senses another presence, one who goes her own way without fear or favor from the unicorns or their enemies. She seems to be protecting him. But why?