History Literature / TheMirrorCrackdFromSideToSide

* CondescendingCompassion: Ms. Knight means well but she considers Ms. Marple too be more old and infirm than she is and behaves accordingly.

* {{Dedication}}: Christie dedicated the book to Margaret Rutherford, who played Miss Marple in the 1961 film ''Film/MurderSheSaid''.

* MedicationTampering: Ella Zielinsky uses an inhaler. After she [[spoiler:makes the mistake of [[TooDumbToLive trying to blackmail the murderer]]]], she gets a lungful of BitterAlmonds.

* ChekhovsParty: Shortly before [[spoiler: Heather was killed by a poisoned drink meant for Marina Gregg, she told Marina and Miss Marple about a previous time where she had snuck out while ill in order to meet Marina during another of her appearances. She infected Marina with German measles, which stunted the development her fetus and forced her to give the child up despite wanting him for years. This is why Marina killed Heather]].

* ExcessiveMourning: Subverted. To explain the how much [[spoiler:Heather's lack of consideration for others must have prevented her from developing a true emotional bond with anyone,]] Mrs. Marple suggests that [[spoiler:Heather's husband, Arthur,]] won't suffer much the widowhood, since [[spoiler:his wife's attitude even with him]] must have led their life as a couple to be quite detached, emotionally.
* FatalFlaw: Heather Badcock is the perfect example of how having multiple virtues can still be not enough if you have a single but important flaw. Being kind and compassionate, but unable to think about how your actions impact others, can still lead you to hurt them. [[spoiler:Heather never meant any harm and still she ended up ruining the life of Marina Gregg and her child, with her recklessness.]]

"''I'' have been knitting''," Miss Marple replied.

* {{Blackmail}}: Attempted separately by [[spoiler:Italian butler Giuseppe and Jason's secretary Ella Zielinsky]]. [[spoiler:Giuseppe is shot after a trip to the bank, while Ella is poisoned with cyanide in her inhaler. Christie ''always'' kills off her blackmailers.]]

** Marina Gregg bought the very same mansion where the corpse was discovered in ''Literature/TheBodyInTheLibrary''.

* ForWantOfANail: The entire novel, which includes three murders, one suicide, and general chaos and grief in St. Mary Mead, stems from a single, seemingly unimportant incident: [[spoiler: Heather Badcock being sick with German measles and going to meet Marina Gregg for an autograph anyway. The same incident also destroyed Marina Gregg's sanity and career, as it led to her unborn child being infected with the illness and coming out mentally and physically impaired.]]

* RippedFromTheHeadlines: The plot is remarkably similar to the real-life tragedy of Creator/GeneTierney, [[spoiler:who contracted rubella while pregnant, resulting in Daria being born premature, deaf, blind, and severely mentally disabled. These problems contributed to (or, perhaps, outright ''caused'') Tierney's own depression and bipolar disorder. About a year later a woman approached Tierney at a party and said that she had sneaked out of her marine base, under a rubella quarantine at the time, to meet her when she appeared at the Hollywood Canteen, a wartime club that catered to service members where Hollywood stars would appear. Tierney simply stared at the woman, then turned and walked away. She later wrote, "After that I didn't care whether I was anyone's favorite actress ever again."]] It should be noted, however, that Christie was asked about the similarity, and claimed she'd never heard about Tierney's story until after ''The Mirror Cracked'' was published.[[note]]Given widespread knowledge of the disease and how good Hollywood studios were at controlling scandals back then, especially one that would be seen as a tragedy rather than a star's misbehavior, it's certainly possible.[[/note]]

* HollywoodOld: Having Creator/AngelaLansbury, famous for starring in ''Series/MurderSheWrote'', play Miss Marple in the film might seem like a very logical move. However, back then, the series waa still four years in the future, and Lansbury by her own admission was 20 years too young for the role.

* AllLoveIsUnrequited: Ella Zielinsky is in love with Jason Rudd, who's married to Marina, especially because Ella is Jason's personal secretary and sees how exhausted he is from caring for his mentally unstable wife all the time. Her affection makes her a suspect, as Marina's death would free Jason to marry her. [[spoiler: But Ella rather foolishly ends up trying to [[BluffingTheMurderer bluff the murderer]] into thinking she knows they're guilty, and ends up getting poisoned to death for her trouble.]]

* ExcessiveMourning: Subverted. Mrs. Marple explains [[spoiler:how much Heather's lack of consideration for others must have prevented her from forming any real bonds with them]] by implying that even [[spoiler:her husband, Arthur Badcock,]] will go through a fairly short period of mourning [[spoiler:after her death]] and then not suffer much from being left alone, since even as a [[spoiler:wife Heather]] was so incapable of taking an interest in [[spoiler:her husband's feelings]] that their life as a couple must have been rather emotionally detached.