When young Brian discovers plans to close a convent of delightfully eccentric nuns, he sets off with them on a wild road trip across New Zealand to save their home.

183 years before the events chronicled in the original trilogy, a sudden attack by Wulf, a clever and ruthless Dunlending lord seeking vengeance for the death of his father, forces Helm Hammerhand and his people to make a daring last stand in the ancient stronghold of the Hornburg. Finding herself in an increasingly desperate situation, Héra, the daughter of Helm, must summon the will to lead the resistance against a deadly enemy intent on their total destruction.