Sixteen children and four adults are killed in a devastating boat crash in Copenhagen. Detective Chief Superintendent Konrad Simonsen is called in, only to discover that this was no accident and that one of the passengers has a very personal connection to the homicide team. Reeling from this revelation and not knowing who to trust, Simonsen follows a trail that eventually leads him to Bosnia and a network of criminal misconduct. All evidence points towards one shady figure: a high-ranking army specialist with a suspicious past. But the more Simonsen digs, the further the truth slips from his grasp.

The remains of a young woman are discovered in a lake north of Copenhagen. Her identity is a mystery and no one, it appears, has reported her missing. After months of fruitless investigation by the local police, the case is handed over to Konrad Simonsen. It soon becomes clear to Simonsen and his team that this unknown woman is the key to a world of trafficking, prostitution and violence. A world where everything comes with a price, no mistake goes unpunished and everyone knows how to keep a secret.

Lying at the bottom of his apartment stairs, a postman is found dead. At first glance, his death appears to be a simple fall, a straightforward accident and the perfect case for Detective Chief Superintendent Konrad Simonsen to return to after a severe heart attack. But when he is called to investigate, new forensic evidence comes to light and something doesn't add up. When life-size images of a girl are discovered plastering the walls of the dead man's attic, the case takes a new and sinister turn. Who is she? Could she be alive? Soon members of the homicide team find themselves delving into the past, but as they approach the truth, Simonsen discovers long-hidden skeletons in his own closet.

Under the heartless vault of Greenland's arctic sky, the body of a girl is discovered. Half-naked and tied up, buried hundreds of miles from any signs of life, she has lain alone for 25 years. When Detective Chief Superintendent Konrad Simonsen is flown in to investigate this horrific murder and he sees how she was attacked, it triggers a dark memory and he realizes this was not the killer's only victim. As Simonsen's team works to discover evidence that has long since been buried, they unearth truths that certain people would prefer stayed forgotten.

One morning before school, two children find the naked bodies of five men hanging from the gym ceiling. The case leads Detective Konrad Simonsen and his murder squad to the school janitor, who may know more about the killings than he is telling. Soon, Simonsen realizes that each of the five murdered men had a dark and terrible secret in common. And when Simonsen’s own daughter is targeted, he must race to find the culprit before his whole world is destroyed.