When their aunt is taken ill, thirteen-year old Annat and her brother are sent from their small coastal town to live with their unknown father. Like Annat, Yuda is a Shaman; a Wanderer with magical powers, able to enter other worlds. As Annat learns more about her powers, the children join their father on a remarkable train journey to the frozen north and find a land of mystery and intrigue, threatened by dark forces and beset by senseless murders that have halted construction of a new tunnel. But Annat's doll, her only remembrance of her dead mother, may hold a dark secret - and when her brother Malchik is kidnapped, Annat and her father must travel onwards to find him before it is too late.
Between uncertain allies, shadowed enemies and hostile surroundings, it is only in the magical kingdom of La Souterraine that they can find answers - and it may be that only a Shaman can save the family and the Goddess.