While vacationing in the Caribbean, Miss Marple finds her quiet retreat interrupted by the sudden, suspicious death of a talkative major who claimed to possess evidence of a murderer. Miss Marple must navigate the social dynamics of a luxury resort to uncover the truth behind the Major's unfinished story. She faces the challenge of operating in an unfamiliar environment where her usual local contacts are absent and the suspects are wealthy, guarded tourists. The narrative utilizes a third-person perspective that centers on Miss Marple's keen observation of human behavior and her ability to connect seemingly unrelated details. She must identify the killer before they strike again to protect the other guests at the resort.

This novel is widely recognized as a quintessential example of Agatha Christie's later work, showcasing her ability to transplant her most famous detective into an exotic setting. Readers and critics frequently highlight the cleverness of the plot and the charm of seeing Miss Marple outside of her usual English village environment. The story is often praised for its atmospheric depiction of the Caribbean and the intricate puzzle that Christie constructs around the Major's death. While some note that the pacing differs from her earlier works, the consensus remains that it is a satisfying entry in the Miss Marple series that maintains the author's signature wit and deductive rigor.