Fresh from maternity leave, Detective Elma finds herself confronted with a complex case, when a man is found murdered in a holiday cottage in the depths of the Icelandic countryside - the victim of a frenzied knife attack, with a shocking message scrawled on the wall above him.
At home with their baby daughter, Sævar is finding it hard to let go of work, until the chance discovery in a discarded box provides him with a distraction.
Could the diary of a young boy, detailing the events of a long-ago summer have a bearing on Elma's case?