When Wrenn stepped away from the Barrows, he never imagined the journey he would take. Banished from the Keep, aided by an owl mage, and alive after the battle by Moon Lake, Wrenn now finds himself facing an even greater challenge. Aided by Sprock, they travel on a mission to rescue Madeline from the certain revenge of Captain Fenrieg, but within the mines beneath the Mooncrest Mountains, Wrenn discovers an ancient power that could threaten their survival even more than King Dak the Strongclawed. On an epic quest to locate the Heart of the Mountain and the Crown of Power, will Wrenn succeed? Avallon now finds itself locked in an intense struggle, and the Barrows will once more know the taste of peculiarities. But will it survive?