Line #136 Creator/AgathaChristie


1	%% Administrivia/ZeroContextExample entries are not allowed on wiki pages. All such entries have been commented out. Add context to the entries before uncommenting them.
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3	[[quoteright:320:https://static.tvtropes.org/pmwiki/pub/images/agatha_chrstie_1949.jpeg]]
4	[[caption-width-right:320:''"Time is the best killer."'']]
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6	->'''Donna:''' Agatha, people love your books, they really do, they're gonna be reading them for years to come.\
7	'''Agatha:''' If only! Try as I might it's hardly great literature, now that's beyond me. I'm afraid my books will be forgotten, like ephemera.
8	-->-- ''Series/DoctorWho'', "[[Recap/DoctorWhoS30E7TheUnicornAndTheWasp The Unicorn and the Wasp]]"
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10	[[UsefulNotes/KnightFever Dame]] Agatha Mary Clarissa Christie (15 September 1890 – 12 January 1976) was the Queen of English MysteryFiction, ranked with Creator/ArthurConanDoyle as the greatest mystery writer of all time. Her stories might perhaps be best described as elaborately-plotted puzzles, full of false identities and faked deaths. She enjoyed a very long career; her first novel, ''Literature/TheMysteriousAffairAtStyles'', was published in 1920, while her final novel, ''Sleeping Murder'', was published posthumously in 1976. Among the best-selling authors of all time.[[note]]The ''[[Literature/GuinnessWorldRecords Guinness Book]]'' says she's sold more books than any other individual author. If you count shorter works, Creator/WilliamShakespeare takes the lead. If corporations are invited, the collected works of Creator/WaltDisney Productions top the list. Regardless, she's sold three billion copies in over 100 languages.[[/note]] As of 2020, Christie still holds the top spot among the [[https://en.wikipedia.org/wiki/List_of_most_translated_individual_authors most-translated authors]] in the world.
11
12	Her principal detectives were:
13
14	* ''Franchise/HerculePoirot'', a retired Belgian police detective turned P.I. Fastidiously neat, he pretended to be a FunnyForeigner in order to put his clients and suspects off their guard. Agatha Christie herself eventually tired of the character, but since fans enjoyed him, she continued to write Poirot stories. He appeared in 33 novels and 51 short stories.
15	* ''[[Literature/MissMarple Miss Jane Marple]]''. Seemingly a fluffy old spinster, her mind was as sharp as her knitting needles; having lived in small towns her whole life, nothing about human nature ever surprised her. She appeared in 12 novels and 20 short stories.
16	* ''Literature/TommyAndTuppence Beresford'', a husband and wife team. Their adventures were more like spy novels than straight mysteries, though they did contain elements of classic detective novels. They appeared in five books: four novels and a short story collection, ''Partners in Crime''.
17
18	Christie also wrote 16 novels which did not feature any of her series detectives. These ranged from traditional mysteries with one-shot detectives to {{Thriller}}s which placed more emphasis on action than detection. The latter were almost universally the most poorly received of Christie's works, while one of the former, ''Literature/AndThenThereWereNone'', is widely regarded as one of her best, even ''the'' best. Six of her novels, which are usually classed as {{Romance}}s, were written under the pseudonym Mary Westmacott.
19
20	While most of the stories are nominally set in the year of publication, in practice they all take place in the time of the GenteelInterbellumSetting. Of Christie's series detectives, only the Beresfords age in real time. Poirot and Marple both begin as elderly characters and over the course of Christie's 56-year career, age roughly 20 years at most. (This matches a line from the final Poirot novel ''{{Literature/Curtain}}'', in which it is stated that it has been "over twenty years" since the first adventure -- the aforementioned ''Mysterious Affair at Styles'', which came out in 1920 and was set during UsefulNotes/WorldWarI.)
21
22	Christie eventually passed away peacefully in January 1976 at the age of 85 from natural causes at her home at Winterbrook House, Wallingford, Oxfordshire.
23
24	Personality-wise, she was extremely introverted and secretive, [[LovesSecrecy sometimes probably even drawing amusement from it]]. It is really indicative of her character that at the end of her play ''Theatre/TheMousetrap'', the viewers are specifically asked not to spoil the ending to outsiders -- Christie possessed an uncanny ability to subvert the reader's expectations. Being well aware of the mystery conventions of the time, she was frequently able to subvert them for a TwistEnding. For example, Christie knew that there were certain characters, who by virtue of their role in the story, the reader would not suspect. To drive home the point that [[EveryoneIsASuspect the reader should suspect]] ''[[EveryoneIsASuspect everybody]]'', she would frequently make one of these characters the murderer. For example:
25
26	[[folder:Twist endings used in Christie's works]]
27	* The ''way'' too obvious suspect ([[TheUntwist who will therefore, of course, turn out not to be the real killer, now will they?]][[invoked]]) really ''was'' the killer after all.
28	* [[EverybodyDidIt Everyone was guilty]].
29	* [[NarratorAllAlong The narrator was guilty]].
30	* [[DetectiveMole One of the sleuths (including the main detective!) investigating the mystery was guilty]].
31	** The guilty party was impersonating the detective.
32	* One of the murder victims was guilty.
33	* The murders looked like the work of an AxCrazy killer, but the murderer was not crazy.
34	* The initial victim was a distraction, and the major intended victim was one of those killed later.
35	* The murder was just a ploy to accuse someone other of it and get them hanged.
36	** The murder was a suicide, arranged by the victim to look like a murder and thus posthumously condemn their enemy.
37	*** The murder was a suicide with no ulterior motives, but someone else decided to frame another person for it to send them to the gallows.
38	* There was no murderer at all.
39	* One of the victims was chosen randomly, despite the murderer being completely sane.
40	** The murderer didn't choose his victim at all.
41	* The seemingly accidental victim was in fact the real target, and the apparently intended target was the murderer.
42	* The murder took place in the narrator's head only.
43	* [[EnfantTerrible The murderer was a child.]]
44	* The SecretCircleOfSecrets are the ''good'' guys.
45	[[/folder]]
46
47	Note that Christie ''invented'' most of the above twist endings.
48
49	For a complete Christie bibliography, including novels, short stories, and stage plays, [[Recap/AgathaChristie see this page.]] Most of the books in the main series have been televised, many filmed, some repeatedly. There's even an ''{{anime}}'' {{Crossover}} of [[Anime/AgathaChristiesGreatDetectivesPoirotAndMarple Poirot and Miss Marple]].
50
51	[[folder:Works by Agatha Christie which have their own pages]]
52	* [[index]]Franchise/HerculePoirot series
53	** ''Literature/TheMysteriousAffairAtStyles'' (1920)
54	** ''Literature/TheMurderOnTheLinks'' (1923)
55	** ''Literature/PoirotInvestigates'' (1924) (short story collection)
56	** ''Literature/TheMurderOfRogerAckroyd'' (1926)
57	** ''Literature/TheBigFour'' (1927)
58	** ''Literature/TheMysteryOfTheBlueTrain'' (1928)
59	** ''Theatre/BlackCoffee'' (1930)
60	** ''Literature/PerilAtEndHouse'' (1932)
61	** ''Literature/LordEdgwareDies'' (1933)
62	** ''Literature/ThreeActTragedy'' (1934)
63	** ''Literature/MurderOnTheOrientExpress'' (1934)
64	** ''Literature/DeathInTheClouds'' (1935)
65	** ''Literature/MurderInMesopotamia'' (1936)
66	** ''Literature/TheABCMurders'' (1936)
67	** ''Literature/CardsOnTheTable'' (1936)
68	** ''Literature/DumbWitness'' (1937)
69	** ''Literature/DeathOnTheNile'' (1937)
70	** ''Literature/MurderInTheMews'' (1937)
71	** ''Literature/AppointmentWithDeath'' (1938)
72	** ''Literature/HerculePoirotsChristmas'' (1938)
73	** ''Literature/OneTwoBuckleMyShoe'' (1940)
74	** ''Literature/SadCypress'' (1940)
75	** ''Literature/EvilUnderTheSun'' (1941)
76	** ''Literature/FiveLittlePigs'' (1942)
77	** ''Literature/TheHollow'' (1946)
78	** ''Literature/TheLaboursOfHercules'' (1947)(short story collection)
79	** ''Literature/TakenAtTheFlood'' (1948)
80	** ''Literature/MrsMcGintysDead'' (1952)
81	** ''Literature/AfterTheFuneral'' (1953)
82	** ''Literature/HickoryDickoryDock'' (1953)
83	** ''Literature/DeadMansFolly'' (1956)
84	** ''Literature/CatAmongThePigeons'' (1959)
85	** ''Literature/TheClocks'' (1964)
86	** ''Literature/ThirdGirl'' (1966)
87	** ''Literature/HalloweenParty'' (1969)
88	** ''Literature/ElephantsCanRemember'' (1972)
89	** ''{{Literature/Curtain}}'' (1975)
90	* Literature/MissMarple series
91	** ''Literature/TheMurderAtTheVicarage'' (1930)
92	** ''Literature/TheThirteenProblems'' (1932)
93	** ''Literature/TheBodyInTheLibrary'' (1942)
94	** ''Literature/TheMovingFinger'' (1943)
95	** ''Literature/AMurderIsAnnounced'' (1950)
96	** ''Literature/TheyDoItWithMirrors'' (1952)
97	** ''Literature/APocketFullOfRye'' (1953)
98	** ''Literature/FourFiftyFromPaddington'' (1957)
99	** ''Literature/TheMirrorCrackdFromSideToSide'' (1962)
100	** ''Literature/ACaribbeanMystery'' (1964)
101	** ''Literature/AtBertramsHotel'' (1965)
102	** ''Literature/{{Nemesis\|AgathaChristie}}'' (1971)
103	** ''Literature/SleepingMurder'' (1976)
104	* Literature/TommyAndTuppence series (1922)
105	** ''Literature/TheSecretAdversary'' (1922)
106	** ''Literature/PartnersInCrime'' (1929)
107	* ''Literature/TheManInTheBrownSuit'' (1924)
108	* ''Literature/TheSecretOfChimneys'' (1925)
109	* ''Literature/TheSevenDialsMystery'' (1929)
110	* ''Literature/TheMysteriousMrQuin'' (1930)
111	* ''Literature/TheSittafordMystery'' (1931)
112	* ''Literature/ParkerPyneInvestigates'' (1934)
113	* ''Literature/WhyDidntTheyAskEvans'' (1934)
114	* ''Literature/MurderIsEasy'' (1939)
115	* ''Literature/AndThenThereWereNone'' (1939)
116	* ''Literature/DeathComesAsTheEnd'' (1944)
117	* ''Literature/TowardsZero'' (1944)
118	* ''Literature/SparklingCyanide'' (1945)
119	* ''Literature/CrookedHouse'' (1949)
120	* ''Literature/TheyCameToBaghdad'' (1951)
121	* ''Theatre/TheMousetrap'' (1952)
122	* ''Film/WitnessForTheProsecution'' (1953)[[note]]The 1957 film was based on Christie's 1953 play, in turn based on her 1925 short story.[[/note]]
123	* ''Literature/DestinationUnknown'' (1954)
124	* ''Theatre/SpidersWeb'' (1954)
125	* ''Literature/OrdealByInnocence'' (1958)
126	* ''Literature/ThePaleHorse'' (1961)
127	* ''Literature/EndlessNight'' (1967)
128	* ''Literature/PassengerToFrankfurt'' (1970)
129	[[/index]]
130	[[/folder]]
131
132	----
133	!!Other works by Agatha Christie include examples of:
134	* AdaptationalAlternateEnding: Christie changed the endings of at least two of her novels when adapting them for the stage.
135	* AllGirlsWantBadBoys: Repeatedly used, mentioned (and complained about) in-universe. In some cases the "bad boy" is the criminal, in others the girl sees sense, and in another a milquetoast character is advised not to tell the truth to his wife, who will love him all the more for thinking she managed to show him the error of his ways.
136	* AmateurSleuth: It would be quicker to list the Christie protagonists who ''aren't'' amateurs: Franchise/HerculePoirot (a former officer of the Belgian police, turned private detective) and Superintendent Battle (a police detective).
137	%%* AmbitionIsEvil: Turns up in several Christie works.
138	* AnyoneCanDie: One plot twist Christie used was to set up a situation in which the reader expects a particular person to die [[AlwaysMurder (because of course we expect somebody to die)]] only for somebody else entirely to get murdered. And sometimes, ''everyone does.''
139	* {{Arcadia}}: Often deconstructed. Christie often places a story in some quiet, beautiful, peaceful rural setting--Arcadia, in other words--then writes of depravity and murder taking place in that same location.
140	* AssholeVictim: On multiple occasions; see the pages for individual works for details. ''Literature/AndThenThereWereNone'' was built on this, with an unknown person luring ten murderers to an island and killing them off one at a time. Another of her most famous works, ''Murder on the Orient Express'', revolves around a victim who was a kidnapper and child murderer.
141	* AuthorAppeal: Christie's second husband was an archaeologist, and Christie eventually developed a strong interest in the subject herself. Not surprisingly, several of her mid-period novels reflect this interest either by taking place at an archaeological dig (''Murder in Mesopotamia'') or by simply having such a setting as the background (''Appointment with Death''). In ''Literature/TheyCameToBaghdad'' the heroine falls in love with an archaeologist. This interest eventually led Christie to actually set one novel in ancient Egypt itself (''Literature/DeathComesAsTheEnd''). Her work on digs ended up making her an expert on Mesopotamian pottery - reportedly, she once asked an archaeologist friend who the greatest authority on a particular kind of pottery was, as she wanted to consult them, only to be told ''she'' was the greatest authority.
142	* AuthorAvatar:
143	** Ariadne Oliver, showing that Dame Agatha didn't take herself too seriously. Ariadne was a popular mystery novelist who often wrote in the bathtub with a dish of apples nearby, as Agatha did herself. Ariadne would try to help Poirot and often made the same mistakes in these "real life" cases as well as in her own writing, that Agatha herself had made in prior books. Oliver frequently laments her vegetarian Finnish detective Sven Hjerson's existence reflecting Agatha Christie's own frustrations with her Belgian NeatFreak.
144	** Before that, there was the one-off Daniel Clancy in Poirot novel ''Death in the Clouds'', who is delighted to be involved in the mystery as it will give him material for his next murder story, and who complains about having to include his detective's weird quirks into every novel.
145	%%* BeautyIsBad: The more attractive a man is, the more his appearance departs from the stuffy, military-ish rough and conservative Englishman, the more immoral he is. Attractive men will be suspected immediately, will usually remind the detectives of other handsome killers they've met, and if they're not the killers, they are likely to be accomplices, blackmailers or withholding evidence because they've acquired it while doing something immoral. Plus, with just a few exceptions, any affection of a handsome man for a woman is false, usually motivated by money.
146	%%** Possibly a case of WriteWhoYouKnow. Christie's first husband was a man like this; the marriage ended very badly.
147	* BewareTheNiceOnes: Part of her technique of dispelling suspicion from the actual murderer is by portraying them as friendly, genial or meek, up until the evidence suddenly becomes obvious.
148	* BadgeGag: One story has the hero accosted by a detective who flashes his badge while investigating a stolen diamond. As he later tells the diamond's rightful owner, he knew the detective was fake as he recognized the badge from his cycling club.
149	* BigScrewedUpFamily: When a case involves the death of a wealthy and influential character, this trope is likely in play. More often than not, the victim is killed for their [[InheritanceMurder inheritance]] by financially insatiable relatives who have no love for said victim, [[EveryoneIsASuspect and everyone is equally likely to be the murderer.]]
150	* BitterAlmonds: Multiple Christie novels involved someone detecting a whiff of bitter almonds as a sign of cyanide poisoning, including, unsurprisingly, ''Sparkling Cyanide''.
151	* {{Blackmail}}: Christie and her sleuths share a great disdain for blackmailers. Often the quickest way to become the next corpse is to [[BlackmailBackfire try and blackmail the murderer]].
152	* BlackmailBackfire: One of Agatha Christie's unspoken rules is that any person trying to blackmail a murderer will be dead before the story ends. If the blackmailer is still alive by the end, it means that a) the person they blackmailed was not a murderer to begin with or b) the blackmail was done as a ruse to trap the killer by agreeing to be TheBait.
153	* BlackSheep: Sometimes appears in BigScrewedUpFamily situations. And in Christie's works their bad reputation often turns out to be well-deserved...
154	* {{Bowdlerise}}: There is a pretty fair amount of racism and anti-Semitism scattered throughout the Christie canon, especially in the early books. Within Christie's lifetime, and indeed within a few years of publication, her masterpiece ''Ten Little N***s'' had the title changed to ''Ten Little Indians''. In later years when that title was recognized as only marginally less bad, the American title, which from the beginning was ''And Then There Were None'', was universally adopted. In the 21st century, new editions of various Christie novels have been controversially [[https://www.theguardian.com/books/2023/mar/26/agatha-christie-novels-reworked-to-remove-potentially-offensive-language edited]] to remove racist and anti-Semitic bits.
155	* TheButlerDidIt: Several times, in different variations, both straight and skewed (for instance: the butler did it, but he wasn't really a butler).
156	* CanonWelding: Christie's main detectives never crossed over, but several minor characters did, effectively tying the majority of her detective fiction into the same universe. For example, the Hercule Poirot mystery ''Literature/DumbWitness'' takes place in Market Basing, a fictitious town featured in the Miss Marple stories.
157	* CelebrityParadox:
158	** In one Poirot novel, a girl mentions having autographs from several crime writers, including Agatha Christie.
159	** Earlier, in ''Partners In Crime'', Tommy and Tuppence solve murders in the style of other literary detectives... such as Hercule Poirot. Possibly an aversion, as Poirot is meant to be a celebrity in the Christieverse.
160	* CerebusRollercoaster: Christie wrote her most serious and psychological works (like ''Literature/FiveLittlePigs'' or ''Literature/TowardsZero'') and two of the novels with the most alarmingly high body count (''Literature/DeathComesAsTheEnd'' and ''Literature/AndThenThereWereNone'') in the middle of her career, in the 1940s. Perhaps it was no coincidence that UsefulNotes/WorldWarII was going on, and war took a toll on her. Her earlier and later stories, are, in general, more lighthearted. Also she wrote ''Curtain'' (Poirot's last novel [[spoiler:ending with his death]]) during that period, as she feared she would not survive the Blitz.
161	* ClearMyName: Multiple works have a case where either someone has directly been accused of a crime and their innocence cannot be proven (in some, their ''guilt'' can't be proven either, but people are still willing to believe it), or there are multiple suspects to a crime but no definite solution, so all of them are under the same cloud of suspicion. Christie often emphasises that it's not just proving them innocent that's important, it's clearing their reputations and/or establishing clearly who the guilty party is, so they can move on with their lives.
162	* ClosedCircle: Used in two of Christie's most famous works. In ''And Then There Were None'' the evil mastermind lures his ten targets to an isolated island, where they are trapped. In ''Murder on the Orient Express'' an avalanche along the track leads to the train being SnowedIn, which allows Poirot to investigate the mystery while the passengers are stuck there.
163	* CluelessMystery: How the clues go together is often made impossible for the reader to divine until the detective states it. A good example is ''4:50 From Paddington'', in which the killer turns out to be the doctor (whom the audience had no reason to suspect), who turned out to have killed his wife (whom the reader has no reason to even suspect exists.)
164	%%** Although the clues ''themselves'' will pretty much always point to the right person. The thing left out is usually details in their motivation.
165	* ConnectTheDeaths: Frequently used as a RedHerring; at least three novels feature murderers setting up a false pattern to conceal the true motive behind the crime. In ''The ABC Murders'' someone kills people with, respectively, the initials AA, BB, and CC, and suspicion is cast on a character with the initials ABC. It's a ruse, as the real killer murdered CC, Sir Carmichael Clarke, for [[InheritanceMurder an inheritance]]. In ''A Pocket Full of Rye'' basically the same thing happens. A killer murders three people in a pattern that matches the NurseryRhyme "Sing a song of sixpence", but it's really an InheritanceMurder.
166	* CourteousCanadian: Canadians tend to be meek, polite, good subjects of the Empire, and are given little other identity of their own. In general, Canada gets off more lightly than [[{{Eagleland}} America]], [[LandDownUnder Australia]], or other parts of the world, and the country is generally treated as simply a repository for British subjects who needed to be out of the country for one reason or another. Young women from families struck by poverty or tragedy are often sent to Canada to stay with relatives; wealthy executives occasionally go there for business.
167	* CoversAlwaysLie: Defied. Christie was greatly displeased with the original artwork for the cover of ''The Man in the Brown Suit''; she felt it was both horribly done and intentionally misleading. From then on, all covers of the original editions required her final approval.
168	* DiscouragingConcealment: [[DiscussedTrope Discussed]] in the Creator/AgathaChristie short story "Strange Jest." Miss Marple recalls her Uncle Henry, who was something of TheGadfly, endlessly bragging about a brand-new, state-of-the-art safe he'd had installed to protect his money. When curious thieves broke in and opened the safe, they found it empty; Uncle Henry had actually concealed his fortune behind a bound collection of old sermons in his library. Miss Marple explains that Uncle Henry knew that no one would willingly take books of that kind off the shelf, making it the perfect hiding place.
169	* DirtyCop: Generally averted. In Christie's verse, police are almost always honest and diligent, if often [[PoliceAreUseless inefficient and prejudiced]]. And that concerns police everywhere, not only in Good Old England: in one of the short stories Poirot scoffs at an Englishman who thought he could bribe Herzoslovakian police to conceal a murder. If some cop turns out to have been dishonest, chances are he is not a real cop to begin with. [[spoiler:Or that you're reading ''Literature/HerculePoirotsChristmas'', though even there "dirty" is probably not the right word. Blore from ''Literature/AndThenThereWereNone'']] might be the sole example in Christie's lore where this trope was played completely straight.
170	* TheDogWasTheMastermind: Christie usually preferred her murderers to be HiddenInPlainSight, but sometimes it turns out to be the one person it couldn't ''possibly'' have been. Notable examples include [[spoiler: the ten year old KidDetective]] in ''Crooked House'', [[spoiler: the victim's elderly, half-blind mother]] in "The Chocolate Box" and [[spoiler: one half of the comic relief duo]] in ''Appointment with Death''.
171	* DrivenToSuicide: Multiple variations. Often it's the murderer killing themselves after they are caught: this happens in ''The Murder of Roger Ackroyd'', ''Nemesis'', and one story in ''The Labours of Hercules'', among others.
172	%%* TheDutifulSon: sometimes appears in BigScrewedUpFamily situations.
173	* DrivesLikeCrazy:
174	** The play ''The Unexpected Guest'' also includes this with the titular guest trying to shift blame in the murder of Richard Warwick to the father of a little boy that Warwick ran over two years before. It is never truly revealed how it happened, only that Warwick is completely unrepentant about the matter, his caretaker did a damn good job keeping him out of jail over it, and that the father was found to be dead not long after the event.
175	** This is what gets Anthony Marston of ''Literature/AndThenThereWereNone'' invited to the deadly island. Well, that and his utter indifference to the children he killed that way.
176	* {{Eagleland}}: As a rather old-fashioned British subject, it should be no surprise that her depictions of Americans in her works were just a little... off (particularly in terms of their accent and [[SeparatedByACommonLanguage any use of idiomatic language]]). In fact, you pick up early on that if one of her characters is American, or is a British subject who spent any significant time there, that person is usually an AssholeVictim, a buffoon, or a weak criminal type. [[spoiler:They are, however, rarely important enough to be the actual murderer.]] And of course, there's [[Literature/MurderOnTheOrientExpress the case where everyone has ties to America]]; [[spoiler:[[EverybodyDidIt they all can't have done it]], right?]]
177	** However, being Agatha Christie, that didn't stop her from averting and subverting this trope. In ''Literature/SparklingCyanide'', for example, [[spoiler:the supposed untrustworthy American character turns out to be a double-agent spy on the side of good, and he also ends up being the one to solve the mystery and prevent the murderer from striking again. The same novel has an example of a British subject masquerading as one of those 'weak criminal type' Americans. He does this in order to slip under the radar of the British detectives - and the radar of any readers too familiar with Christie's other works.]]
178	* TheEndingChangesEverything: Naturally, it occurs to some extent in quite a few works, but the most prominent examples are probably ''Literature/TheMurderOfRogerAckroyd'', ''The Unexpected Guest'' and ''Literature/EndlessNight''.
179	%%* EnfantTerrible: [[spoiler:Josephine Leonides in ''Crooked House'']].
180	* EverybodyDidIt: She wrote the Trope Maker for ''this'' one too. [[spoiler:In ''Murder on the Orient Express'', the passengers have all deliberately conspired to act as a de facto jury and execute a man who evaded justice in the States. They all knew the victim's family and are only pretending to be strangers in order to deliberately obfuscate the means by which the man was killed and corroborate each others' false alibis.]]
181	* EveryoneIsASuspect: One of the central tenets of Christie's body of work. In most of her books, it truly feels that ''any'' of the characters could be guilty.
182	* EveryoneMustBePaired: Several of Christie's books ends with all the remaining suspects after the arrest of the murderer getting hooked up with each other, regardless of their previous interactions. ''Towards Zero'' and ''Appointment With Death'' are some examples.
183	* {{Expy}}:
184	** After noting how much she enjoyed writing the gossipy spinster Caroline Sheppard in ''The Murder of Roger Ackroyd'', Christie decided to revamp this character into someone who would become a fixture in her work -- [[LittleOldLadyInvestigates nosy-but-wise]] [[Literature/MissMarple Miss Jane Marple]].
185	** Several of the non-series books feature "Bright Young Thing" detective couples who are expies of Tommy and Tuppence. The 1982 ITV production of ''Partners in Crime'' {{lampshade\|Hanging}}d this by having Tommy and Tuppence played by the same two actors who played Bobby Jones and Frankie Derwent in their 1980 adaptation of ''Why Didn't They Ask Evans?'' Between the two, James Warwick (Tommy and Bobby) also played Jimmy Thesiger in the 1981 adaptation of ''The Seven Dials Mystery'', although opposite Cheryl Campbell as Bundle, rather than Fransesca Annis. [[spoiler:And Jimmy is a subversion of the "Tommy-style" character, since he turns out to be the murderer]].
186	** AuthorAvatar Ariadne Oliver's most popular character, Sven Hjerson, is a thinly-disguised expy of Poirot. He's lanky and Finnish rather than plump and Belgian, and [[PickyEater a vegetarian who grates his vegetables]] rather than being a NeatFreak, but his creator's in-universe complaints mirror Christie's growing dislike of Poirot in real life. In 2021, Sweden's [=TV4=] actually made a Hjerson series with the full blessing of the Christie estate.
187	** It is outright stated in ''Literature/SparklingCyanide'' that Inspector Kemp is basically a less competent version of Battle. Kemp used to work under the former Superintendent and has adopted many of his mannerisms.
188	* FairPlayWhodunnit: She was one of the most successful worldwide practitioners of this, although ''Literature/TheMurderOfRogerAckroyd'' sparked a major controversy over its fairness. [[spoiler:It was accused of not being fair as the narrator, who for this novel only replaced Hastings as TheWatson, turns out to be the killer. It's now generally considered to be extremely fair, as the narrator never lies ''to the reader'' about his motivations or actions, but simply leaves his actions at the time of the killing un-described in a way that is easy to pass over the first time but glaring upon a second reading.]]
189	* FakeMystery:
190	** In ''Dead Man's Folly'', Hercule Poirot gets an urgent phone call from Ariadne Oliver, telling him that a crime is about to be committed at the mansion where she's staying. When he rushes to get there, it turns out that she was [[ExactWords speaking literally]]--Oliver has been invited to create a mystery-puzzle game for an upcoming town fair hosted at the mansion, and she wanted Poirot to come down and make sure that what she's written is a good crime. It's then [[SubvertedTrope subverted]] when the girl hired to play the "corpse" in Oliver's fake mystery actually gets murdered during the game, leading Poirot to investigate her death
191	** In "The Theft of the Royal Ruby," Poirot is staying at a manor for Christmas after receiving a tip that the titular jewel is going to be stolen by thieves. The teenagers who are also at the manor think that Poirot must be bored and decide to stage a fake murder to cheer him up. It's [[SubvertedTrope subverted]] when Bridget, who volunteered to play the corpse, actually ''does'' get murdered as part of the scheme to steal the ruby. But after the crook is exposed, Poirot reveals it was a [[DoubleSubverted double subversion]]: he overheard the teens planning their caper and, with Bridget's help, arranged for her to [[FakingTheDead pretend to be dead]] so that the criminals would give themselves away.
192	*** In the same story, Poirot receives an anonymous note that reads "DON'T EAT NONE OF THE PLUM PUDDING" and suspects that an attempt is being made on his life. At the end of the adventure, he still hasn't figured out why the note was left--and then one of the housemaids confesses that she overheard the criminals talking about getting him out of the way, followed by the remarks "Where did you hide it?" "In the pudding." They were actually discussing the hiding place for the ruby, but the maid thought that the crooks planned to poison Poirot with the dessert and sent him the anonymous message to warn him.
193	** In "The Adventure of Johnny Waverly," the prominent Waverly family hires Poirot to solve the kidnapping of their son, who was taken after several threatening messages were sent to their home. After investigating, Poirot quickly determines that it was Mr. Waverly who arranged the entire thing in an attempt to bilk his wealthy wife out of a huge ransom, as he lacks any actual funds himself.
194	* FramingTheGuiltyParty: Multiple instances, described on their respective pages.
195	* GenreSavvy: Take a shot every time someone compares the current situation to a mystery novel, or even rules out a possibility based on its likelihood in fiction. And then hope you have a strong liver.
196	* GenteelInterbellumSetting: ''The Mysterious Affair At Styles'' was written during World War I and published shortly thereafter, and the majority of Christie's novels are set in the homes of the leisured upper class, in mansions and on estates, at parties, dinners, and vacation spots. Even later novels often follow older characters clinging to the last vestiges of those days once they are long-gone, or reminiscing upon them in the lean years following World War II. So exemplary of the era was Christie that [[TropeNamers the trope was originally named]] "Christie Time", as a reference to ComicBookTime -- the era, in Christie's novels, lasted far longer than it did in the real world, and with it her two most famous detectives (both said to already be elderly when they were introduced). Later books do reference the changing times; the final two books, however -- ''Literature/{{Curtain}}'' and ''Sleeping Murder'' -- were written in the middle of World War II and never revised, creating a sense of SnapBack when they were published upon Christie's death. ''Literature/AtBertramsHotel'' even serves as a deconstruction; the eponymous hotel exudes old-world charm and hearkens back to a bygone era, only to be revealed as [[spoiler:the front for a criminal syndicate.]]
197	* GolfClubbing: Subverted as an important clue in [[spoiler:''Literature/TowardsZero'', in which the murder was actually committed with, much more unusually, a tennis racket.]]
198	* GreedyJew: Christie often relied on the pre-War stereotypes of Jews as somehow "other" in her stories and novels, though she rarely goes into truly offensive territory. After World War II, Christie went back and retroactively edited the most offensive language out of her earlier books; she did, however, sometimes leave in a character's anti-Semitism as a hint that we're not supposed to like him.
199	* HaveAGayOldTime: Naturally. One of the most prominent examples comes from Poirot's short story titled "The Adventure of the Western Star":
200	** ''"That's queer," I ejaculated suddenly beneath my breath.''
201	* HeKnowsTooMuch: The surest way for an Agatha Christie character to sign his own death warrant is by attempting to blackmail a killer. Also goes for anyone who didn't know that they knew anything significant, or who didn't know the whole story but knew something vital. Basically, if you're in an Agatha Christie novel, you'd better hope and pray that you either don't have a major part, don't find anything out, aren't confided in by anyone; or if you do find something out, you know how to ''keep your mouth shut''. (See series and works pages for specific examples.)
202	* HeroicRussianEmigre: Agatha had quite conservative political views, typical for her epoch: she disliked Bolshevism and tended to portray post-1917 Russian émigrés in a generally sympathetic light, though also recognizing that the chaotic situation often gave life to spurious claims to non-existent nobility status by various impersonators. Examples of the émigrés include "Countess" Vera Rossakoff, Franchise/HerculePoirot's only acknowledged love interest, and Princess Natalia Dragomiroff from ''Literature/MurderOnTheOrientExpress'' [[spoiler:who was a {{Vigilante\|Man}} seeking to avenge [[WouldHurtAChild the murder of a child]], and was acquitted by Poirot.]]
203	%%* HeroicWannabe: William Smith in ''Murder on the Nile'' (''Death on the Nile'' play counterpart), constantly trying to win the heart of Christina Grant.
204	* {{Inspiration For the Work}}: Agatha Christie herself (not just her famous characters) has inspired numerous works even decades after she died. For example, there was a mystery novel called Literature/TheAgathas released in 2022 where one of the two lead characters is obsessed with Agatha Christie’s books and life. In fact, every chapter has a different quote of Christie’s.
205	* InvisibleWriting: Two short stories (one featuring Hercule Poirot and one Miss Marple), involve rich eccentrics writing their {{will\|AndInheritanceTropes}} in Invisible Ink, and challenging the heirs to find it.
206	* LandDownUnder: Showing something of her Victorian upbringing, Australia (and sometimes South Africa) is home to criminals and unscrupulous adventurers, seemingly as a holdover from its founding [[SentencedToDownUnder as a British penal colony]]. Like {{Eagleland}}ers, they are often portrayed as foolish, backward, or morally lax compared to ''proper'' Englishmen and women. Many of her blackmailers and servants who steal from their employers spent time in Australia, as if the country itself attracted criminals. The CorruptCorporateExecutive in Christie books often made their fortune in one or the other, such as Simeon Lee in ''Literature/HerculePoirotsChristmas'' having discovered a number of diamond mines in South Africa. In ''Literature/SadCypress'' the villain has spent time in New Zealand and at some point [[spoiler:she]] had to leave very quickly, to avoid being arrested.
207	* LaserGuidedKarma: The short story "Wireless", in which [[spoiler:Charles's plan to kill his aunt and inherit the money he needs to avoid prison directly results in the accidental destruction of her will, preventing him from inheriting. Moreover, it turns out if he had done nothing she would have died in about two month's time, rendering his scheme unnecessary]].
208	* LateArrivalSpoiler:Christie's novels occasionally revealed the solutions of previous works, a habit which vexed her publishers. See the Franchise/HerculePoirot page for several examples.
209	** One of the characters in ''The Pale Horse'' is one of the suspects from ''Literature/CardsOnTheTable''. If you read the former first, you'll know he can't be the guilty party in the latter. Which wouldn't be such a big deal if it weren't for the fact that ''Literature/CardsOnTheTable'' was a play with EveryoneIsASuspect where the total number of four, and only four, suspects could've committed the murder (and the murderer is one of the four). If you read ''The Pale Horse'' first, then you only have three suspects.
210	* LoveAtFirstSight: Many of the romantic developments in Christie's stories develop very rapidly when two people meet and are immediately consumed by passion for each other.
211	* LoveHurts: A trope that became a favourite of Agatha's after her divorce from her first husband. When love wasn't driving a character to [[LoveMakesYouEvil commit murder]], it was guaranteed a broken heart from one side or the other. Generally, only a few pairings survive amidst the body counts and broken hearts.
212	%%* LoveMakesYouEvil: ''Oy.'' To list all examples would be ludicrous.
213	%%* LukeIAmYourFather: Turns up quite a lot, usually to provide a motive.
214	* {{Malaproper}}: Poirot's tendency to mangle English idioms is something of a RunningGag.
215	* MarketBasedTitle: Many of her books received new titles for the US market. All are now published under the UK titles with the exception of ''And Then There Were None'', which has also become the official title in the UK - the previous title of ''Ten Little Indians''[[note]]originally ''Ten Little N***s''[[/note]] no longer being socially acceptable (for obvious reasons).
216	* TheMatchmaker: Both Hercule Poirot and Miss Marple display a tendency at times to play matchmaker in the lives of two lovers who need to be brought together during their investigations.
217	* MetaTwist: Almost from the beginning, her various twist endings relied on a degree of familiarity with the conventions of the FairPlayWhoDunnit so that she could subvert them. This includes the characters in the books themselves, [[spoiler:such as the murderer, [[NarratorAllAlong who is also the narrator]] (as early as her [[Literature/TheMurderOfRogerAckroyd third Poirot novel]])]], discussing and often dismissing the tropes of mystery fiction. Given [[PrintLongRunners the longevity and popularity of her work]], Christie was able to also manage readers' expectations based on the formulas present in her own work, as in [[spoiler:''Literature/{{Curtain}}'', in which Poirot, devoutly Catholic and having spent his whole life catching murderers, ''commits'' a murder himself to stop a murderer who has escaped all other attempts to bring him to justice.]]
218	* MurderByMistake:
219	** Played straight in [[spoiler:''Sparkling Cyanide'' and ''Literature/ACaribbeanMystery'']], the former as a result of an accidental switch of glasses, and the latter as a result of the killer incorrectly identifying someone in the dark.
220	** Inverted more frequently, however, with murderers managing to fool everyone into thinking that this trope occurred. Killers in [[spoiler:''Literature/PerilAtEndHouse'', ''Literature/TheMirrorCrackdFromSideToSide'', ''Literature/AtBertramsHotel'' and the short story ''Triangle at Rhodes'']] even make themselves look like the intended victims, while [[spoiler:''Literature/ThreeActTragedy'' and ''Literature/TheABCMurders'']] each feature an apparently misdirected murder in which it turns out that the killer murdered someone at random and didn't even care who it was.
221	* MurderSuicide: A not-uncommon resolution has the murderer kill themselves at the end of TheSummation, [[BetterToDieThanBeKilled preferring to die on their own terms]] rather than face the gallows, or the publicity of a trial. [[spoiler:The killer in ''Peril At End House'' opts for an overdose of cocaine hidden in a wristwatch; one of the two murderers in ''Death on the Nile'' shoots her accomplice, then herself -- out of love.]]
222	* NecroCam: Most of her work's film/television adaptations include at least one 'true' (and usually several 'false') version of this as the detective crosses off potential theories in the finale.
223	** ''Film/DeathOnTheNile2022'': As Poirot puts things together, his deductions about how the crimes went down are presented in DeliberatelyMonochrome flashbacks. One example is the scene where Bouc witnesses Louise murdered, then chucks his coat (splattered with arterial blood) into the river.
224	** ''Film/MurderOnTheOrientExpress1974'': During Poirot's [[TheSummation summation]] we get visuals of what he thought happened on the night of the murder.
225	%%* NeverFoundTheBody
226	* OddballInTheSeries: The Hercule Poirot novel ''Literature/TheBigFour''. It's most concisely described as Poirot in a ''Franchise/JamesBond''-style SpyFiction mystery, battling an evil alliance bent on world domination, consisting of an English MasterOfDisguise, a French MadScientist, an American CorruptCorporateExecutive, and a YellowPeril mastermind.
227	* PairTheSpares: Even when Poirot or Miss Marple aren't actively playing matchmaker, there's still a good chance of a romantic pairing in the background.
228	* PoliceAreUseless: Although Christie's depictions of the police force is usually more positive than the usual examples of the trope, they never seem to be able to solve a case quickly enough without the aid of the amateur sleuths or "outsider". They also frequently arrest the wrong person, forcing the star detective(s) to act quickly before an innocent gets hanged for the crime. Naturally averted in the case of the Superintendent Battle novels.
229	** One of the most extreme cases of this trope is the Hercule Poirot’s short story "The Adventure of the Italian Nobleman", which starts off with a physician receiving a weird phone call supposedly from his patient. The patient is soon found dead in his home, and it’s [[BlatantLies blatantly obvious]] to everybody, including [[TheWatson Hastings]], that the phone call was actually made by the killer impersonating the victim. However, the only suspect was seen leaving the victim’s home long before the phone call was made. [[spoiler:Turns out the killer made the phone call from a random phone booth after he had committed the murder and left the victim’s home. The police were so lazy and incompetent, they didn’t even bother to check the phone number from which the call came, and instead they just assumed it was made from the victim’s home.]]
230	** In the short story "The Edge", the protagonist convinces a woman she loathes to kill herself by way of blackmail, but is so horrified at what she's done that she immediately confesses to the crime. Because multiple people saw the victim kill herself with nobody else around, the protagonist is deemed insane and is institutionalised. The police had to have been involved at some point, but apparently nobody- police, doctor, witness or anyone else- bothered asking the protagonist ''why'' she was so adamant that she was responsible.
231	%%* RedRightHand: [[spoiler:Josephine Leonides' general appearance]] in ''Crooked House''.
232	* SameFaceDifferentName: Christie also wrote six romance novels under the name Mary Westmacott.
233	* SheIsAllGrownUp: Between ''Literature/TheSecretOfChimneys'' and ''Seven Dial Mysteries'', Eileen "Bundle" Brent has grown from being "just a kid" to a very eligible young woman pursued by both George Lomax and Bill Eversleigh.
234	* ShownTheirWork: Christie worked as a druggist during World War I and became an expert on poisons and how they worked, and she never missed an opportunity to show this knowledge off. In ''The Pale Horse'', published in 1961, her descriptions of thallium poisoning were detailed to the point [[https://www.independent.co.uk/news/science/the-poison-prescribed-by-agatha-christie-thanks-to-the-mystery-writer-the-deadly-properties-of-thallium-sulphate-have-become-common-knowledge-corrected-1534450.html that it helped solve a case that was baffling doctors.]]
235	** As noted under AuthorAppeal above, Christie was also an expert in Mesopotamian and Egyptian artifacts and culture; her second husband was an archeologist, and she often accompanied him on his trips to those regions of the world, allowing her to do research firsthand and incorporate it into her stories.
236	* SlidingScaleOfAnthropomorphism: There are a couple of times in the books when the narrative switches to a dog's point of view, with the dogs coming somewhat close to the "Intellectual Animal" point - examples include Bob from ''Literature/DumbWitness'' and half a page from ''Literature/TowardsZero''.
237	%%* SpousalPrivilege: A plot point in ''Witness for the Prosecution''.
238	* StartToCorpse: On the long side, with Christie's murders sometimes not taking place until halfway through the book. This tendency toward [[SlowPacedBeginning Slow-Paced Beginnings]] is discussed in-universe in ''Literature/TowardsZero'', making the point that a murder is much more than the event itself -- it's all the interactions and pressures leading up to it which inform the motive, and so (in the opinion of Christie's mouthpiece character) a murder mystery ''should'' leave the actual death as late as possible, giving the reader a window into the lives of the victim and suspects.
239	** Conversely, several of her books have short start-to-corpses. ''Literature/TheBodyInTheLibrary'', for example, begins with the staff of a house waking up the owners to inform them that a corpse has been discovered in their library.
240	* StockForeignName: In Christie's verse, it seems that every Italian guy is named Giuseppe. One is a hotel attendant in ''The Secret of Chimneys'', one is the head waiter of a restaurant in ''Literature/SparklingCyanide'', while one serves as a butler for the Cleggs in ''The Mirror Crack'd from Side to Side''. Averted in ''Literature/MurderOnTheOrientExpress'', which makes a one-line reference to a Wagon-Lits waiter named Pietro and has a prominent character named Antonio.
241	* StoppedClock: Used several times, in works featuring various detectives. More often subverted (e.g. it turns out the murderer set it up to mislead the detective about the time of death) than played straight.
242	* SuicideNotMurder: Played with in the novels, though NeverSuicide ultimately wins out 99% of the time. Occasionally one of a series of deaths will turn out to be a suicide [[spoiler:(such as in ''Dumb Witness'')]], but there is always at least ''one'' genuine homicide in each full-length novel. However, [[spoiler:in the short stories "The Market Basing Mystery" and "Murder in the Mews", as well as the stage adaptation of ''Appointment With Death'', the alleged suicides actually do turn out to be suicides in the end]].
243	* SympatheticMurderer: Christie's plots often work on a sliding scale: if a character is an AssholeVictim, expect the murderer to be treated well; if the victim was TooGoodForThisSinfulEarth, then the murderer would be remorselessly evil. The most extreme example is probably ''Murder on the Orient Express'', where the villain is a man who kidnapped and murdered a child, causing a disastrous chain effect that killed at least two other people, and the murderer [[spoiler:or rather ''murderers'' are twelve people directly affected by those deaths, prompting them to seek revenge.]] Even Poirot, who normally holds murderers in contempt regardless of their justifications, [[EveryoneHasStandards decides to let this killer go free]], coming up with another solution to satisfy the authorities.
244	%%* TakingTheHeat: Both played straight and subverted.
245	%%* TapOnTheHead: Multiple instances.
246	* TenLittleMurderVictims: The TropeNamer and TropeMaker -- ''Literature/AndThenThereWereNone'' was originally titled ''Ten Little Indians''.[[note]]And before that ''[[ValuesDissonance Ten Little N***s]]''[[/note]] Ten strangers are invited to a private island, are revealed to be murderers who had gone unpunished for their previous crimes, and are then [[DwindlingParty murdered one by one]] by an unknown killer who presumably must be one of the ten.
247	* TerminallyIllCriminal:
248	** ''Literature/AndThenThereWereNone'': The BigBad learns that he has cancer and resolves to kill several people who were acquitted of their crimes despite their certain guilt. He ends up committing suicide after all the others are dead, having previously faked his death to continue the murders unimpeded.
249	** ''Franchise/HerculePoirot'':
250	*** "Wasp's Nest": A man named Harrison, who is diagnosed with terminal cancer, plots to commit suicide after leaving clues that will lead to his romantic rival being blamed for his "murder" and hanged for it. Poirot discovers and foils his plan by replacing the poison he used to kill himself with baking soda and chews out the man because his plan was effectively attempted murder. Harrison accepts the admonishment and makes peace with the fact that his ex-lover had chosen the other guy.
251	*** ''{{Literature/Curtain}}'': Poirot himself commits murder to remove a sociopath capable of inciting people to murder for his own sick amusement, and his confession only comes to Hastings after his death of natural causes (that is, not taking the medicine for his heart condition).
252	* ThemeNaming:
253	** Christie was fond of titling her works after nursery rhymes. Novel examples include ''Literature/AndThenThereWereNone'' (and both its [[MarketBasedTitle previous titles]]); ''One, Two, Buckle My Shoe''; ''Literature/FiveLittlePigs''; ''Crooked House''; ''Hickory Dickory Dock''; and ''A Pocket Full of Rye''. Short stories include "Sing a Song of Sixpence", "Four and Twenty Blackbirds", "How Does Your Garden Grow", and "Three Blind Mice". Note that each of the first three lines of "Sing a Song of Sixpence" has provided the title of a work.
254	** She also enjoyed the occasional LiteraryAllusionTitle, with several works referencing famous poems and plays. ''Postern of Fate'' and the short story "The Gate of Baghdad" both came from the first quarter of the poem Gates of Damascus by James Elroy Flecker. ''The Mirror Crack'd From Side To Side'' is from the [[Creator/AlfredLordTennyson Tennyson]] poem "The Lady of Shalott". ''Sad Cypress'', ''Taken at the Flood'' and ''By the Pricking of My Thumbs'' are all Creator/WilliamShakespeare.
255	%%* {{Tontine}}: Several of her books rely on them.
256	* TooDumbToLive: It's frequently lampshaded that a person who has already gotten away with murder once is much less likely to stick at killing again [[HeKnowsTooMuch to protect their secret]], which makes {{blackmail}} an exceptionally foolish pursuit in such cases.
257	* TwistEnding: As mentioned in the description, Christie is generally held to have invented a number of twist endings in her books, including, most famously, [[spoiler:[[EverybodyDidIt the entire body of suspects conspiring together]] in ''Literature/MurderOnTheOrientExpress'' and [[NarratorAllAlong the narrator being the murderer]] in ''Literature/TheMurderOfRogerAckroyd''.]]
258	* TwoDunIt: Many of Christie's stories have two killers working together. Her favourite twist was having a man and a woman [[ReverseRelationshipReveal pretend to hate each other]] or [[WeDoNotKnowEachOther not know each other]], only for it to be revealed that they are [[SecretRelationship secretly lovers]] who are covering for each other by providing alibis and murder opportunities. It's sometimes also revealed or hinted that one of the murderers was planning to (and sometimes successfully does) [[YouHaveOutlivedYourUsefulness kill their partner in crime afterwards]]. A more rare version is that one of the culprits were tricked or strong-armed into working with the other murderer against their will.
259	* ATrueStoryInMyUniverse: There are references in multiple Poirot novels to Captain Hastings, Poirot's frequent narrator, writing books about Poirot's cases--the novels in the series themselves. Dr. Sheppard, the narrator in ''Literature/TheMurderOfRogerAckroyd'', says that he is writing the book because he read Hastings's books and was inspired by them.
260	* UpperClassTwit: Aristocrats are often depicted in Christie's books as silly and self-absorbed, something which Superintendent Battle lampshades in ''The Secret of Chimneys''. Examples of this are Sir Eustace Pedler (''The Man In Brown Suit'') and Lord Caterham (''Secret of Chimneys'' & ''Seven Dials Mystery''), who, in their respective novels, whines about how inconsiderate people are for dying in their properties and causing them a lot of trouble due to the subsequent scandals that occur. Even Bundle, who is a lot more sensible than her family, briefly expresses indignation when she finds out that the first victim of ''Seven Dials'' died in ''her'' room.
261	* TheVerse: Although Christie withstood public demands and never put Poirot and Marple in a story together, there was enough {{crossover}} among the lesser characters to show that they both lived in the same world. For instance,
262	** St. Mary Mead, Miss Jane Marple's fictional home village, was first mentioned in 1928 Poirot novel ''Literature/TheMysteryOfTheBlueTrain''. In that book it's the home of protagonist Katherine Grey.
263	** A minor character, Mr. Robinson, appeared briefly with both Poirot (''Cat Among the Pigeons'') and Miss Marple (''At Bertram's Hotel''), as well as in ''Passenger to Frankfurt'', which featured neither of them. He also appears in ''Postern of Fate'', with Tommy and Tuppence.
264	** ''The Pale Horse'', which does ''not'' feature Poirot or Miss Marple, does feature Mr. and Mrs. Dane Calthorp (who had appeared in Miss Marple novel ''Literature/TheMovingFinger'') along with Ariadne Oliver, who appears in several Poirot novels, and [[spoiler:Major Despard]], one of the suspects from the Poirot novel ''Literature/CardsOnTheTable.'' [[spoiler:Rhoda Despard née Dawes]] also appears in both ''Cards on the Table'' and ''The Pale Horse''.
265	** Speaking of Ariadne Oliver, she first appeared as a supporting character to [[Literature/ParkerPyneInvestigates Parker Pyne]], one of Christie's lesser-known detectives; as did another of Poirot's supporting cast, Miss Felicity Lemon.
266	** Colonel Race, who also appears as a supporting character in two novels with Hercule Poirot (''Death on the Nile'' and the aforementioned ''Literature/CardsOnTheTable''), but also in ''Literature/TheManInTheBrownSuit'' and ''Literature/SparklingCyanide'' (which are not Hercule Poirot novels).
267	** Another of Christie's lesser-known detectives, the elderly Mr Satterthwaite, collaborates with Poirot in the novel ''Three Act Tragedy'' and briefly appears at the start of the Poirot short story "[[Literature/MurderInTheMews Dead Man's Mirror]]", which ties the supernatural-themed [[Literature/TheMysteriousMrQuin Harley Quin stories]] into the universe.
268	** The Beresfords have clearly heard of Hercule Poirot enough to make jokes about him and pretend to be him while solving a case in ''Partners in Crime'', and in ''The Secret Adversary'' they meet Poirot's friend Inspector Japp, [[spoiler: or someone pretending to be him]].
269	** Superintendent Battle of Scotland Yard, a supporting character in the Hercule Poirot novel ''Literature/CardsOnTheTable'' who is also mentioned in Poirot novel ''Literature/HerculePoirotsChristmas'', is the main sleuth in one-off novel ''Towards Zero'' (where he reminisces on Poirot).
270	** While as noted above the Poirot, Marple, Parker Pyne, Harley Quin and Tommy & Tuppence series are all tied together, and several of Christie's one-off books are tied in with them, there are a few one-off Christie novels that do not have an explicit link with the main Christie universe. One of them is possibly her most famous book, ''Literature/AndThenThereWereNone''.
271	* WrongGuyFirst: In several of Christie's stories, two suspects begin to fall in love, only for one of them to be revealed as the murderer.
272

Context Creator / AgathaChristie