Captain Arthur J. M. Hastings, OBE, is a fictional character created by Agatha Christie as the companion-chronicler and best friend of the Belgian detective Hercule Poirot.

Many of the early TV episodes of Agatha Christie's Poirot were adaptations of short stories, in most of which he appeared in print.

Hastings appears to have been introduced by Christie in accordance with the model of Sherlock Holmes's associate, Doctor Watson, to whom he bears a marked resemblance.

Similarly to Watson, Hastings also has a penchant for speculation and gambling, as well as a military background in the colonial Middle East.

In the earlier phase of his career, Hastings is valued for his imaginative approach to cases, inevitably giving rise to fanciful hypotheses that Poirot gently mocks.

Ah ce cher Hastings, at this moment, today, I miss him..." Later in her career, Christie's apparatus is less fanciful and the opportunity for wild speculation much diminished.

Hastings represents the traditional English gentleman—not too bright but absolutely scrupulous, a throwback to the Victorian-era gentleman who is always concerned about "fair play".

Whenever Hastings suggests the innocence of a young, beautiful, female murder suspect, Poirot slyly asks "Does she have auburn hair?"

Despite his preference for auburn hair and his Victorian ideas about not marrying outside one's class, he eventually falls in love with a dark-haired music-hall actress, singer and acrobat Dulcie Duveen, the self-styled 'Cinderella'.

Hastings's appearances in Poirot's later novels are restricted to a few cases in which he participates on his periodic returns to England from Argentina.

The novel culminates with Poirot dying of a heart attack, leaving Hastings a confession explaining his role in events as he tracked a criminal who manipulated others to commit murder for him.

In the postscript of Curtain, Poirot suggests that Hastings should consider a second marriage with Elizabeth Litchfield, the younger sister of a woman who was manipulated into killing her abusive father by the novel's antagonist.

Age is not specifically discussed for Hastings after the first book; he is said to be 30 in The Mysterious Affair at Styles, which would leave him at least 60 years old in the earliest setting for Curtain.

These two facts place the events of Curtain in time no later than 1954, and Hastings is therefore, as he says himself, "I'm pushing it a bit"; with four adult children and having done service in the First World War, he must be in his 60s.

Hastings has been portrayed on film and television by several actors, Richard Cooper in Black Coffee (1931) and Lord Edgware Dies (1934); Robert Morley in The Alphabet Murders (1965); Jonathan Cecil in three TV films – Thirteen at Dinner (1985), Dead Man's Folly (1986) and Murder in Three Acts (1986); Dmitry Krylov in the Soviet film Mystery Endhauz (1989, directed by Vadim Derbenyov); and Hugh Fraser, who portrayed Hastings alongside David Suchet's Poirot in 43 of the 70 episodes of Agatha Christie's Poirot.

In the BBC Radio 4 dramatisations starring John Moffatt as Hercule Poirot, Captain Hastings was played by Jeremy Clyde in Murder on the Links (1990),[8] and by Simon Williams in Lord Edgware Dies (1992), The ABC Murders (2000), Peril at End House (2000), The Mysterious Affair at Styles (2005), and Dumb Witness (2006).