Hercule Poirot met his lifelong friend, Captain Arthur Hastings, and solved the first of his cases to be published, "The Mysterious Affair at Styles". It is clear that Hastings and Poirot are already friends when they meet in Chapter 2 of the novel, as Hastings tells Cynthia that he has not seen him for "some years". Particulars such as the date of 1916 for the case and that Hastings had met Poirot in Belgium, are given in "Curtain: Poirot's Last Case", Chapter 1. After that case, Poirot apparently came to the attention of the British secret service and undertook cases for the
Hercule Poirot as he had been to her: a great detective, a remarkable man, if, perhaps, just now and then, a little irritating. I think back to Poirot’s last words in the scene before he dies. That second ‘Cher ami’ was for someone other than Hastings. It was for my dear, dear friend Poirot. I was saying goodbye to him as well — and I felt it with all my heart. The writers of the "Binge!" article of "Entertainment Weekly" Issue #1343–44 (26 December 2014 – 3 January 2015) picked Suchet as "Best Poirot" in the "Hercule Poirot & Miss Marple" timeline.