The Mysterious Affair at Styles by Agatha Christie (1921)

Given the 2021 centenary of Christie's first published novel, The Mysterious Affair at Styles, I decided I'd start a read of all the Poirot books she wrote. Styles was Poirot's debut, an unfortunate one as it happened since Christie made him an elderly retiree. She didn't expect to still be writing about the character 50 years later, by which time he'd be around 120 if you estimate his age in Styles to be 70 or so. (She'd go on to make the same mistake ten years later with the debut of Miss Marple, an elderly spinster.) This makes Styles a slight anomaly among her works in one way, as unlike later novels it's attached to a specific era: post-World War I. The t...