As Autumn deepens into darkness in Lidingö, on the Stockholm archipelago, the island is plunged into chaos: in the space of a week, two teenagers, the son of the island's mayor and that of a powerful businessman, are brutally murdered. Their bodies are left deep in the forest, dressed in white tunics with crowns of candles atop their heads, like offerings to Saint Lucia. Maïa Rehn has fled Paris for Lidingö, where her husband has grown up, trying to come to terms with the death of their only daughter in a car accident. But when the murders shake the island community, the former police commissioner is drawn into the heart of the investigation, joining Commissioner Aleksander Storm to unravel a mystery as chilling as the Nordic winter. As they dig deeper, it becomes clear that a wind of vengeance is blowing through the archipelago, unearthing secrets that are as scandalous as they are inhuman. But what if the victims weren't who they seemed? What if those long silenced had finally found a way to strike back? How far would they go to make their tormentors pay? And you – how far would you go?