A Caribbean Mystery

Incredibly contrived opening chapter. A doctor suspected a man of murder, and just happened to accidentally take a snapshot of him. Then just happened to carry that snapshot around with him. Then just happened to pass that snapshot and the story on to the major, who then just happens to carry it around with him so that he can tell the story to Miss Marple.

Once you get past that, it's decent enough entertainment, and to be fair even though it was spelled out early on, I still didn't have a clue who the murderer was right up to the moment of reveal.