Nemesis (Marple, Book 12) by Agatha Christie
When Miss Marple receives a letter from the recently deceased millionaire Jason Rafiel, shes not sure what to make of it.
Knowing her deductive skills, he challenges her to solve a crime. If she does so, she will inherit 20,000.
The only problem is that he has failed to mention who was involved, or where, and when the crime was committed. Jane Marple is intrigued.
Never underestimate Miss Marple
Sorry Poirot, but Im team Marple every time. A mind to rival the great Sherlock Holmes and much handier with a knitting needle yet patronised and underestimated by those around her, her invisibility is her superpower. That and her uncanny understanding of the darkest depths of human nature . . .
Lucy Foley
Her gift is pure genius.
Observer