In the middle of a hard-won morning nap in the basement of police headquarters, Carl Mřrck, head of Department Q, receives a call from a colleague working on the Danish island of Bornholm. Carl is dismissive at first, but then he receives some shocking news. Carl then has no choice but to lead Department Q into the tragic cold case of a vivacious seventeen-year-old girl who vanished from school, only to be found dead hanging high up in a tree.