The discovery of a Nazi medal in a deceased mother's belongings triggers a dangerous investigation into long-buried family secrets. Erica Falck, a crime writer, attempts to reconcile her difficult childhood by examining her mother's wartime diaries, only to find that her inquiries threaten those around her. As she navigates the evasive accounts of her mother's former associates, a violent murder forces her husband, Detective Patrik Hedström, to abandon his paternity leave to pursue the killer. The narrative shifts between the present-day investigation and the shadows of the past, creating a dual-timeline structure that heightens the tension surrounding the family's history.

This novel is widely recognized as a staple of the Nordic Noir genre, praised for its ability to weave complex historical threads into a contemporary police procedural. Readers often highlight the author's skill in balancing the domestic challenges of the protagonists with the grim reality of the crimes they investigate. The atmospheric setting of a small Swedish coastal town serves as a backdrop that mirrors the cold, hidden nature of the secrets being unearthed. The narrative's focus on the darker aspects of human history and the lingering effects of war provides a substantial emotional weight to the mystery. The work is regarded as a successful continuation of the series, maintaining the established tone and character dynamics that fans of the genre expect.