As Prince Gwydion lay close to death, terror filled Taran for he saw that Dyrnwyn, the black sword and enchanted weapon of ancient power, no longer hung at the Prince's side. Stolen by the evil Huntsmen, it must now be in the power of Arawn himself, lord of Annuvin, land of the Dead. So, in his greatest and most important quest, Taran prepares to confront Arawn's terrible cohorts, in the final struggle to save Prydain from permanent darkness.