A shocking attack on a politician in Reykjavik means Chief of Police Andri has to return to his hometown in the north of the island, and to working with his former colleagues Hinrika and Asgeir, to investigate a suspected link between the case and far-right nationalists. Things are changing in the countryside. Heavy industry is taking over, to the deep resentment of local farmers and environmentalists, with fears of untold damage to both their livelihoods and their landscape. With Andri's family life still fractured since the dark events three years ago that sent him to Reykjavik, he is going back to a place that still feels strange to him.

Ketill is released, but his sons Torfi and Skuli remain the best lead the police have. With Skuli still on the loose, a full search-and-rescue operation is mounted. Torfi drops a hint that his group, Hammer of Thor, are planning something big, but do Andri and Hinrika have time to work out what it is before it's too late? Asgeir helps them make a breakthrough. Meanwhile Mayor Hafdis is still being threatened by a mysterious opponent, but is determined to conceal it from the police until the investment deal is signed.