A brutal murder discovered in a shipping crate off the coast of Wales launches Inspector French into a complex investigation. Inspector Joseph French is called to Burry Port after two fishermen find a crate containing a decomposing body. With no immediate identification for the victim or the crate's origin, the local police enlist the help of Scotland Yard. French, known for his meticulous approach, believes no case is truly insoluble and begins to meticulously examine the scant clues. His investigation will uncover the identity of the victim and the circumstances surrounding his violent death, leading him through a labyrinth of deceit and danger.

This novel is a classic example of Freeman Wills Crofts's meticulous plotting and logical deduction, a hallmark of Golden Age detective fiction. Readers familiar with Inspector French will recognize his signature thoroughness as he meticulously pieces together the evidence. The mystery is built on a foundation of realistic detail and a steady, unhurried pace, rewarding patient readers with a satisfyingly complex resolution. The narrative focuses on the 'how' and 'why' of the crime, presenting a puzzle for the reader to solve alongside the inspector.