A richly layered detective novel by Robert Galbraith, published in 2020. It is the fifth novel in the Cormoran Strike and is widely regarded as one of the strongest and most ambitious entries in the series.

Private investigator Cormoran Strike is approached by Anna Phipps, whose mother, Dr. Margot Bamborough, vanished without a trace in 1974. Although the disappearance is nearly forty years old and the police long ago gave up hope, Anna wants to know what really happened.

Despite believing the case may be impossible to solve, Strike and his business partner Robin Ellacott begin re-examining the old investigation. They uncover forgotten witness statements, anonymous letters, missing records, and long-buried secrets. Their search leads them through decades of lies, family conflicts, professional rivalries, and hidden relationships.

One of the central threads of the investigation involves the notorious serial killer Dennis Creed, who was active during the period of Margot's disappearance. However, the novel avoids simple answers, weaving together multiple suspects and motives into an intricate mystery.

Alongside the investigation, the book continues to develop the personal and professional relationship between Strike and Robin, adding emotional depth without overshadowing the central case.