The World's End — Agatha Christie

Previously published in the print anthology The Mysterious Mr. Quin.

Mr. Satterthwaite has come to Corsica with his friend the Duchess of Leith. There they meet the Duchess's cousin Naomi Carlton-Smith. Distraught that her fiancé has been accused of stealing, Naomi turns to Satterthwaite and the mysterious Mr. Quin for help.