When a body of a woman is discovered at a lighthouse in the Icelandic town of Akranes, it soon becomes clear that she’s no stranger to the area. Chief Investigating Officer Elma, who has returned to Akranes following a failed relationship, and her collegues Sævar and Hörður commence an uneasy investigation which uncovers a shocking secret in the dead woman’s past that continues to reverberate in the present day.

Freshly trained detective Johannes "Hannes" Niehaus is brand new to the Criminal Investigation Department. And his partner, unconventional veteran detective Fritz Janssen, isn't the least bit thrilled to train a rookie. When a woman's body washes up on the nearby shores of the Baltic Sea, Hannes gets his first taste of real crime - and a chance to prove himself. Quickly the investigation pulls him and Fritz into a whirlpool of dangerous, decades-old cover-ups.

When a boy leaps to his death from a bridge in the northern town of Umeå, Sweden, police discover drugs scattered in the snow near his body. The town has seen a dramatic increase in narcotic use among its youth, but nobody knows where the pills are coming from.

On the day Stockholm police officer Hanna Ahlander’s personal and professional lives crash, she takes refuge at her sister’s lodge in the Swedish ski resort paradise of Åre. But it’s a brief comfort. The entire village is shaken by the sudden vanishing of a local teenage girl. Hanna can’t help but investigate, and while searching for the missing person, she lands a job with the local police department. There she joins forces with Detective Inspector Daniel Lindskog, who has been tasked with finding the girl. Their only lead: a scarf in the snow. 

Fresh from maternity leave, Detective Elma finds herself confronted with a complex case, when a man is found murdered in a holiday cottage in the depths of the Icelandic countryside - the victim of a frenzied knife attack, with a shocking message scrawled on the wall above him.