"One must not put a loaded rifle on the stage if no one is thinking of firing it." – Anton Chekhov, letter to Aleksandr Semenovich Lazarev (pseudonym of A. S. Gruzinsky), 1 November 1889.
It is a metaphor for a plot device or foreshadowing, which if shown or discussed should be used later.
A false clue that leads the characters toward an inaccurate conclusion within the plot of a story, considered to be the opposite of Chekhov’s Gun.
The Chewbacca Defense is starting to come into the lexicon as a famous Red Herring It refers to a South Park episode and refers to using something so patently absurd that it makes no sense and creates confusion.
"[We] have a name in the studio, and we call it the 'MacGuffin'. It is the mechanical element that usually crops up in any story. In crook stories it is almost always the necklace and in spy stories it is most always the papers".
-- Alfred Hitchcock
A plot device that provides the initial motivation for a character, and it may or may not end up coming back into the story at the end.
Deus ex machina
Latin for: God from the machine.
This device goes all the way back to ancient Greece, where a problem in the story is solved by the sudden invention of something that saves the day. It’s often criticized as lacking imagination on the part of the author, as it often violates the internal logic of a story.
The Tommy Westphall Universe Hypothesis
A character from television series St Elsewhere who, in the last episode was seen waking up and the entire series was in his imagination. Refers to using the “it was all a dream” idea to end a story.
Alien Space Bats
The term was originally used as a sarcastic attack on poorly written alternate histories due to lack of plausibility to create improbably plot divergences. Also refers to the use of Deus ex Machina in the form of Ancient Aliens.
A plot device where the exact verbal directions are followed to the letter but avoid its intended meaning, such as: A deal with the Devil, or Genie Wishes, or in The Lord of the Rings, Glorfindel's prophecy states that "not by the hand of man will the Witch-king of Angmar fall." The Witch-king is slain by Éowyn, a woman.
Retroactive continuity or Retcon
An alteration of facts about a story that already been published in order to accommodate a sequel or prequel, or simply to correct errors in the original chronology of events.
Commonly used in Comic Books and Pulp Fiction.
Big Dumb Object (BDO)
The science fiction term refers to any mysterious object (usually of extraterrestrial or unknown origin and immense power) in a story which generates an intense sense of wonder just by being there. For example the Monoliths in 2001 A Space Odyssey, or The Void Ship in Doctor Who.
A neologism that gives a new name to an old object because of some development that requires clarification, such as Acoustic Guitar after the Electric Guitar was developed.
Same as an acronym but the word came first and the meaning behind the letters followed after.
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