Erica Campbell returns to Villa Skasen for Sofie's wedding and a final confrontation with the powerful witch, Marte Vilhunen, self-proclaimed Tietaja and Dragonmoon of Finnskogen. As their feud escalates, war becomes inevitable and draws in the Forest Trolls, the mysterious Viitri clan and the lake dragon. But before Erica can accept her calling as Dragonmoon, she must destroy the witch at the Battle of Aga'In. It soon becomes apparent that Marte cannot be killed and Erica risks losing everything unless she can find a way to defeat the witch and banish her from the Black Cottage."