# Hercule Poirot — The Big Four character guide > Hercule Poirot in The Big Four by Agatha Christie. **Role:** major **Also known as:** M. Hercule Poirot, M. Poirot, Mr. Poirot, Mr. Hercule Poirot, Moosior Poirot, Monsieur Poirot, Monsieur Hercule Poirot **First appearance:** 0000-i-the-unexpected-guest ## Who they are A Belgian detective with waxed moustaches and unshakable method, who alone insists a four-headed criminal conspiracy is real while governments dismiss him as a monomaniac. ## Relationships ### [Inspector Japp](https://www.betterreads.dev/discover/the_big_four_se/characters/inspector_japp) _professional_ Poirot and Japp have a professional working relationship as detective and police inspector, often collaborating on cases with mutual respect. ### [Flossie Monro](https://www.betterreads.dev/discover/the_big_four_se/characters/flossie_monro) _professional_ Flossie Monro is a client or witness who interacts with Poirot in the context of the investigation. ### [Madame Olivier](https://www.betterreads.dev/discover/the_big_four_se/characters/madame_olivier) _rivalry_ Madame Olivier is a formidable antagonist and member of the Big Four, opposing Poirot's efforts to dismantle the criminal organization. ### [Abe Ryland](https://www.betterreads.dev/discover/the_big_four_se/characters/abe_ryland) _rivalry_ Abe Ryland is a powerful member of the Big Four and a direct adversary to Poirot's detective work. ### [Mrs. Halliday](https://www.betterreads.dev/discover/the_big_four_se/characters/mrs_halliday) _professional_ Mrs. Halliday is a client or person of interest in the case, interacting with Poirot as part of the investigation. ### [Dr. Savaronoff](https://www.betterreads.dev/discover/the_big_four_se/characters/dr_savaronoff) _professional_ Dr. Savaronoff is a scientist or expert consulted by Poirot in the course of the mystery. ### [Mr. Paynter](https://www.betterreads.dev/discover/the_big_four_se/characters/mr_paynter) _professional_ Mr. Paynter is a character involved in the plot, likely a suspect or witness interacting with Poirot. ### [Number Four](https://www.betterreads.dev/discover/the_big_four_se/characters/number_four) _rivalry_ Number Four is a key member of the Big Four, a dangerous enemy working against Poirot. ### [Li Chang Yen](https://www.betterreads.dev/discover/the_big_four_se/characters/li_chang_yen) _rivalry_ Li Chang Yen is a mastermind of the Big Four, a cunning and powerful adversary of Poirot. ### [Dr. Ridgeway](https://www.betterreads.dev/discover/the_big_four_se/characters/dr_ridgeway) _professional_ Dr. Ridgeway is a medical professional or expert who assists Poirot with forensic or scientific matters. ### [Halliday](https://www.betterreads.dev/discover/the_big_four_se/characters/halliday) _professional_ Halliday is a character connected to the case, possibly a suspect or relative of a victim, interacting with Poirot. ### [John Ingles](https://www.betterreads.dev/discover/the_big_four_se/characters/john_ingles) _friendship_ John Ingles is an ally and friend who aids Poirot in his investigation against the Big Four. ## In the story ### [The Unexpected Guest](https://www.betterreads.dev/discover/the_big_four_se/chapters/i-the-unexpected-guest) Preparing to leave for South America on a lucrative case for Abe Ryland, but is drawn into the mystery of the Big Four when a stranger arrives at his flat. ### [II: The Man from the Asylum](https://www.betterreads.dev/discover/the_big_four_se/chapters/ii-the-man-from-the-asylum) Deduces the train diversion was a plot to get him out of the way; investigates the murder of Mayerling; realizes the killer is Number Four. ### [We Hear More About Li Chang Yen](https://www.betterreads.dev/discover/the_big_four_se/chapters/iii-we-hear-more-about-li-chang-yen) Dismisses Hastings' hope of the fake attendant returning; visits Mr. Ingles to learn about Li Chang Yen; decides to travel to Dartmoor after reading Whalley's letter. ### [IV: The Importance of a Leg of Mutton](https://www.betterreads.dev/discover/the_big_four_se/chapters/iv-the-importance-of-a-leg-of-mutton) Leads the investigation, deduces the murderer's method using the frozen leg of mutton, and secures Grant's release. ### [V: Disappearance of a Scientist](https://www.betterreads.dev/discover/the_big_four_se/chapters/v-disappearance-of-a-scientist) Investigates Halliday's disappearance, deduces the Big Four's involvement, and decides to travel to Paris. ### [The Woman on the Stairs](https://www.betterreads.dev/discover/the_big_four_se/chapters/vi-the-woman-on-the-stairs) Leads the investigation into Halliday's disappearance in Paris, interviews Madame Olivier, and deduces the involvement of the Big Four. ### [VII: The Radium Thieves](https://www.betterreads.dev/discover/the_big_four_se/chapters/vii-the-radium-thieves) Remains in Paris after Halliday's release, sees through the Big Four's bribery attempt, and plans to protect Madame Olivier's radium. ### [In the House of the Enemy](https://www.betterreads.dev/discover/the_big_four_se/chapters/viii-in-the-house-of-the-enemy) Poirot suspects Ryland is Number Two, devises the infiltration plan, and later deciphers the coded message, though the trap backfires. ### [IX: The Yellow Jasmine Mystery](https://www.betterreads.dev/discover/the_big_four_se/chapters/ix-the-yellow-jasmine-mystery) Poirot is investigating the Paynter case, using it to take a break from his obsession with the Big Four. He remains confident and methodical. ### [X: We Investigate at Croftlands](https://www.betterreads.dev/discover/the_big_four_se/chapters/x-we-investigate-at-croftlands) Investigates the death of Mr. Paynter, deduces the significance of 'Yellow Jasmine' as a poison, and identifies Dr. Quentin as the murderer. ### [XI: A Chess Problem](https://www.betterreads.dev/discover/the_big_four_se/chapters/xi-a-chess-problem) Dines with Hastings and Japp; deduces the murder method involving an electrified chess piece and links it to the Big Four. ### [The Baited Trap](https://www.betterreads.dev/discover/the_big_four_se/chapters/xii-the-baited-trap) Discusses the investigation with Hastings, then leaves the room; Hastings leaves a sign for him. ### [The Mouse Walks In](https://www.betterreads.dev/discover/the_big_four_se/chapters/xiii-the-mouse-walks-in) Deciphers Hastings' warning signs, arrives prepared with a smoke bomb and police, rescues Hastings. ### [XIV: The Peroxide Blonde](https://www.betterreads.dev/discover/the_big_four_se/chapters/xiv-the-peroxide-blonde) Leads the investigation, deduces Number Four is an actor, and vows revenge after Flossie Monro's death. ### [XV: The Terrible Catastrophe](https://www.betterreads.dev/discover/the_big_four_se/chapters/xv-the-terrible-catastrophe) Reveals the Big Four to officials, prepares for his death, and is killed by a bomb in his lodgings. ### [Number Four Wins a Trick](https://www.betterreads.dev/discover/the_big_four_se/chapters/xvii-number-four-wins-a-trick) In hiding in the Ardennes, Poirot plans to resurrect himself and gather the Big Four together for a final strike. He interprets Hastings' account of Ingles's servant's dying words to deduce the meeting place at Karersee. ### [In the Felsenlabyrynth](https://www.betterreads.dev/discover/the_big_four_se/chapters/xviii-in-the-felsenlabyrynth) Revealed to have been impersonating his 'twin brother' Achille; orchestrates the cordon and rescue, and later explains his full plan. ## Links - HTML: https://www.betterreads.dev/discover/the_big_four_se/characters/hercule_poirot - Book: https://www.betterreads.dev/discover/the_big_four_se - All characters: https://www.betterreads.dev/discover/the_big_four_se/characters