Red Vipereen, an evil wizard, is bent on taking over Prince Rupert’s world-famous stable of horses. Madame Fosse, the palace psychic, predicts that Edwin Goodchild is the only one who can help them. No-one believes her, least of all Edwin’s sister, Holly. How could her eleven-year-old, wimpy brother help anyone? What Holly doesn’t know is that Edwin possesses a magical gift with horses. And when Black of Sainglend, the prince’s most prized horse, is stolen, it is Edwin who leads a search party across the treacherous Grindsniff Wastelands to find him.