One-Horn's daughter is not like the other satyricorns. Born of a human father, she has failed to grow the horns so prized by her kind. Soon the satyricorns will kill her – and even if she runs away, their swift hunters will find her in the end.
When she sees a herd of magnificent winged horses flying over her home in the high mountains, she finally sees her chance. If she could only capture one of the legendary flying horses, and stay on its back long enough to fly far away, she might escape.
So begins a journey that will take her towards danger, death, love and betrayal – and give her a new name: Rhiannon, the rider that none can catch.
Travelling with a group of apprentice-witches through a land where the dead walk and ghosts haunt the living, Rhiannon can sense what her human companions cannot: there are dark walkers about, and those who would wish ill upon Eileanan. But can the humans trust the word of a wild and fierce satyricorn girl?