It was the island where Mia Kruger once came to end her own life. Years later, Mia has returned to the picturesque Hitra, reconciling the trauma of her twin sister's death and ready to live a quiet life away from the police force. But when she is approach by 11-year-old Sofia asking for help in finding her missing friend, the investigator inside Mia is awakened. Three years ago, Jonathan disappeared without a trace on his way home from Sofia's house. As Mia begins to re-examine the cold case, another crime rocks the island: a teenage girl is found brutally murdered, with Jonathan's name written in her blood. Desperately trying to connect the two cases, Mia calls in her former boss Holger Munch to join the investigation. With tensions building in the locals of Hitra as more bodies are discovered, Munch and Mia must reunite to navigate the deadly maze of the island before the elusive killer claims their next victim.