A love triangle between Dan Sommerdahl, his wife Marianne Sommerdahl and their best friend Flemming Torp occurs as they try to solves killings in Helsingør.

Denmark, 2016. A blurred note is found in a bottle that has traveled across the ocean for a long time. After deciphering the cryptic note, Department Q follow a sinister trail that leads them to investigate a case that occurred in 2008. At the same time, new tragic events take place that test their faith and deepest beliefs.

Kasper's parents are divorced. Every other weekend he takes the train between Jutland and the capital with a group of other children. Kasper finds it difficult to make friends, but he has a talent for rapping and it gives him a strong connection with another outsider Tobias, who makes music on his computer. On the train the two boys make a rap CD for a pretty girl named Marie. It turns out that her father is a famous judge on a popular talent show on television. That opens up new opportunities for boys, but it also creates jealousy among the popular kids in the railway car.