“Poirot has most of the characteristics that the British of the time were supposed to despise in bourgeois foreigners. He is vain, fussy, dapper and conceited enough to expect that everyone has heard of him and admires him. Yet it is vital that he is acceptable as a foreign hero to the readers. So although he has the veneer of a foreigner, he possesses the manners, social graces, values and sentiments so important to the British. His friendship with a proven British loyalist, Captain Hastings, also endorses his credibility.”
– Cathy Cook, The Agatha Christie Miscellany