Nemesis by Agatha Christie..In utter disbelief, Jane Marple read the letter addressed to her from the recently deceased Mr Rafiel - an acquaintance she had met briefly while on vacation in St. Honore, as recounted in "A Caribbean Mystery." Rafiel had left instructions for her to investigate a crime after his death. The only problem was, he had failed to tell her who was involved or where and when the crime had been committed.
It was most intriguing. Soon she is faced with a new crime - the ultimate crime - murder. It seems someone is adamant that past evils remain buried.
Librarian's note: this entry is for the novel, "Nemesis." Collections and other Miss Marple stories are located elsewhere on Goodreads. The series includes 12 novels and 20 short stories. Entries for the short stories can be found by searching Goodreads for: "a Miss Marple Short Story."