The latest case for Cormoran Strike and Robin Ellacott - the cleverest detective duo in British crime fiction. After Robin Ellacott receives a mysterious package, she is horrified to discover that it contains a severed female leg. Her boss, private investigator Cormoran Strike, is also disturbed, but hardly surprised. Four people from his own past come to mind, any of whom he could believe capable of such an act - and Strike knows that each of them is capable of ruthless, unspeakable cruelty. While the police focus on a single suspect, who Strike increasingly doubts could be the perpetrator, he and Robin take matters into their own hands and venture into the dark and disturbing worlds of the other three men. But as more shocking incidents shake London, everything spirals out of control.