Revenge is a destructive fire. Revenge among the gods and goddesses can engulf the world.

Such is the threat that Dara and her friends confront. Sparked first by Dara's father's theft of the cauldron of Ceridwen, unleashed by that cup's return, storms of anger collided in Scotland, unwittingly destroying the ancient home of the goddess of winter, Cailleach. Only an elven queen saw this destruction. Only she imagined a way to placate that goddess' anger.

Cailleach had given the Grail, a seeing-stone, to a trusted druid leader before the days of King Arthur. That stone was passed on to Merlin. Just before King Arthur's tragic last battle, Merlin passed it on to the harper Taliesen who accompanied Lancelot to France to defend Brittany against the invading Goths. Taliesen and Lancelot's story, and the story of the Grail's hiding, is told alongside the modern quest. The goddess of winter will forgo her revenge if the Grail is returned.

Dara and her friends take on this seemingly impossible task with the aid of an elf and the guidance of the Triad who carry on the responsibilities of King Arthur. But landing in France places them in the middle of ancient conflicts that threaten their quest at every step. As winter draws closer Britain, as snow traps hikers and threatens the natural cycle, the four friends race to retrace Taliesen's steps and find the Grail.