The Keeper of Lost Causes (2013) 

Synopsis

Based on the first book in Jussi Adler-Olsen's bestselling thriller series about Department Q THE KEEPER OF LOST CAUSES tells the story of the two policemen Carl Mørck and Assad who become involved in a five-year-old case concerning a missing woman, Merete. Soon Carl and Assad are on a journey through Scandinavia's darkest corners to find a psychopathic killer.