Keeper of Lost Causes. Department Q 1, Paperback/Jussi Adler-Olsen

Copenhagen detective Carl Morck has been taken off homicide to run a newly created department for unsolved crimes. His first case concerns Merete Lynggaard, who vanished five years ago. Everyone says she's dead. Everyone says it's a waste of time. He thinks they're right. The voice in the dark is distorted, harsh and without mercy.