Which Agatha Christie novel is set on the fictional island of St Honoré?

"A Caribbean Mystery" is a work of detective fiction by British writer Agatha Christie, first published in the UK by the Collins Crime Club on 16 November 1964 and in the United States by Dodd, Mead and Company the following year. This story takes place at the Golden Palm resort on the fictional Caribbean island of St Honoré. Miss Marple's nephew has paid for her to holiday there after a bout of ill health.

During her holiday one of the guests, the elderly Major Palgrave, is found dead. The death is put down to natural causes until one of the maids finds medication belonging to another guest in the late major's room. When the maid is also found dead it is clear that the Major's oft-repeated tale of knowing a murderer convinces Miss Marple that the murderer is someone at the hotel.

Dame Agatha Mary Clarissa Christie (15 September 1890 – 12 January 1976) was an English writer known for her 66 detective novels and 14 short story collections, particularly those revolving around fictional detectives Hercule Poirot and Miss Marple.

She also wrote the world's longest-running play, "The Mousetrap", which has been performed in the West End since 1952, as well as six novels under the pseudonym Mary Westmacott. In 1971, she was made a Dame (DBE) for her contributions to literature. "Guinness World Records" lists Christie as the best-selling fiction writer of all time, her novels having sold more than two billion copies.