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 to Hastings, it was chosen by Poirot "entirely on account of its strict geometrical appearance and proportion" and described as the "newest type of service flat". (The Florin Court building was actually built in 1936, decades after Poirot fictionally moved in.) His first case in this period was "The Affair at the Victory Ball", which allowed Poirot to enter high society and begin his career as a private detective. Between the world wars, Poirot travelled all over Europe, Africa, Asia, and half of South America investigating crimes and solving murders. Most of his cases occurred during this time and he