1983

At a former sanatorium in the north of Iceland, now a hospital ward, an old nurse, Yrsa, is found murdered. Detective Hulda Hermannsdottir and her boss, Sverrir, are sent to investigate her death. There, they discover five suspects: the chief physician, two junior nurses, a young doctor, and the caretaker, who is arrested following false testimony from one of the nurses, but subsequently released.

Less than a week after the murder, the chief physician, is also found dead, having apparently fallen from a balcony. Sverrir, rules his death as suicide and assumes that he was guilty of the murder as well. The case is closed.

2012

Almost thirty years later, Helgi Reykdal, a young police officer, has been studying criminology in the UK, but decides to return to Iceland when he is offered a job at the Reykjavik police department--the job which detective Hulda Hermannsdottir is about to retire from.

He is also a collector of golden age detective stories, and is writing his thesis on the 1983 murders in the north. As Helgi delves deeper into the past, and starts his new job, he decides to try to meet with the original suspects. But soon he finds silence and suspicion at every turn, as he tries to finally solve the mystery from years before.