There are, roughly speaking, three kinds of consistency that a viewer expects from a story:
- External Consistency: Consistency with the real world.
The fictional universe is Like Reality Unless Noted. Violations of external consistency are "unrealistic."
- Genre Consistency: Consistency with other fictional works.
The fictional universe should behave like other works in its genre, unless specifically noted otherwise. Any fictional concepts, characters, or settings borrowed from other works should behave as they do in those works. Tropes are Played Straight. For example, a dragon is generally expected to be a flying reptilian creature that breathes fire; if it's different in your work, the differences should be pointed out before they start affecting the plot.
- Internal Consistency: Consistency with itself.
Any rules, events, settings, or characters that have been established within the fictional work continue to exist and function as they did previously, unless otherwise indicated. If your work takes place in an Expanded Universe, you're generally expected to be consistent with the (non-expanded) Canon.
Consistency aids Willing Suspension of Disbelief, while violations of consistency may be jolting and unexpected, which can benefit both humor and drama. The viewer would be quite surprised to learn that in your universe, Hitler was a circus performer, dragons are scared of fire, and that the married couple no longer recognize each other in Act III. Generally, if a work is inconsistent, the viewer expects there to be a good reason for it. On the other hand, sometimes violations of consistency go unnoticed even if they're quite obvious, or may even be expected; e.g. The Coconut Effect violates External Consistency.
Often, a feature in a work is consistent at one level and not at another; for example, maybe your vampires glitter in sunlight, which is not genre consistent with other works featuring vampires, but as long as they always do that, it is internally consistent. If a work forgoes External Consistency in favor of Genre Consistency, you have The Coconut Effect. If conversely a work forgoes Genre Consistency in favor of External Consistency, then you have Reality Ensues.
Sometimes, as in the case of sequels, it can be unclear whether two works are distinct works or part of the same work, making the distinction between Genre Consistency and Internal Consistency a bit fuzzy.
No examples please — this is just a descriptive Super-Trope and index.
- Deconstruction: A work looks at the serious reactions and consequences to a work's conventions that are usually glossed over.
- Deliberate Values Dissonance: A work set in the past deliberately shows the unpleasant beliefs and aspects of the past and doesn't whitewash any of it.
- Like Reality Unless Noted
- Plausible Deniability
- Reality Ensues: The realistic consequences and outcomes of certain tropes are demonstrated rather than having the same results as in any other work of fiction.
- Shown Their Work: It is apparent that whatever subject is referenced or used in the work, the creators did thorough research to ensure they made no mistakes about the subject.
- Anime Reality
- Artistic License
- Based on a Great Big Lie
- Celebrity Paradox: Presumably, a movie's actors and other works they starred in don't exist in the setting of the movie.
- Critical Research Failure: It is obvious that the creators did not do their research properly because the information the work gives is blatantly wrong.
- Dan Browned: Insisting you've done the research when it's obvious you didn't.
- Hollywood Style: An index on how things are unrealistically portrayed by Hollywood.
- The Kids Are American: Characters have American accents even though their parents are not American.
- Mutually Fictional: It's established that two works are works of fiction in each other's realities.
- No Endor Holocaust
- Not Allowed to Grow Up: Characters who are children or teenagers never age regardless of how long the series lasts.
- Politically Correct History: Works taking place in the past change or remove aspects of the past that today's people would find offensive or politically incorrect.
- Rule of Index
- This Index Is Anachronistic
- Very Loosely Based on a True Story
- Ascended Glitch
- Continuity Nod: Referencing the events of a previous episode or installment.
- Character Rerailment: Consistent with original characterization at the expense of later characterization.
- Developers' Foresight: Video game developers are able to anticipate anything the player might try to do in the game.
- Jigsaw Puzzle Plot
- Magic A Is Magic A
- Minovsky Physics
- Sliding Scale of Gameplay and Story Integration: The higher a game is on this scale, the more internally consistent it is.
- The Producer Thinks of Everything
- Universe Bible
- Video Games and Fate
- World Building
- Abandoned Catchphrase: A phrase a character frequently said initially, but later stops saying or doesn't say as often anymore.
- Animation Bump: Moments in an animated work where the animation is of a higher quality.
- Ass Pull: An explanation or solution that comes out of nowhere and completely disregards what the story has already established, named from the idea that the author just pulled an answer from their ass out of desperation for a quick and easy way to resolve the conflict.
- Ball Index: When a character briefly acts inconsistently (referred to in these tropes as "holding the [trait] ball") for the sake of the plot.
- Bellisario's Maxim: "Don't examine this too closely." Paying too much attention to the inconsistencies can be to a work's detriment.
- Beyond the Impossible
- Breaking Old Trends
- Broad Strokes: A sequel or reboot establishes that the events of older stories happened, but not necessarily in the exact same way as depicted in the original stories.
- Character Derailment
- Character Rerailment: Inconsistent with later characterization in favor of original characterization.
- The Chris Carter Effect: If too many inconsistencies build up, the audience could leave.
- Continuity Drift
- Continuity Snarl
- Depending on the Artist: A character's physical appearance changes depending on which artist is drawing them.
- Depending on the Writer: A character's personality, interests and so on change depending on who is writing the current episode.
- Discontinuity Nod: Characters make a disparaging reference to a reviled part of the franchise.
- Deus ex Machina
- Fridge Logic: Inconsistencies the audience only realizes after the fact (as in when they're going to the fridge for a snack).
- Gameplay and Story Segregation: What is established in the game's story is not consistent with what is possible or apparent in the actual gameplay.
- Handwave: A work gives a token acknowledgement and dismissal of an inconsistency.
- Inconsistent Coloring
- Inconsistent Dub
- In Name Only: An adaptation that is so different from the source material that the title is pretty much the only thing the two works have in common.
- Moral Dissonance: An action is okay if the good guys do it, but unacceptable if the bad guys do it.
- Negative Continuity: A work lacks a consistent canon, so essentially every episode contradicts each other.
- Off-Model: A character has an inconsistency in their character design.
- Out-of-Character Moment: A moment where a character's behavior contrasts strongly with how they usually act.
- Plot Hole: A story has an inconsistency with the plot preventing it from making complete sense.
- Retcon: Making retroactive changes to the established continuity.
- Series Continuity Error: The series that one points makes a very noticeable continuity error that is too glaring to overlook or excuse.
- Shocking Swerve
- Timey-Wimey Ball: Very often, Time Travel is just plain not consistent.
- Unreliable Canon
- A Wizard Did It: Hastily explaining inconsistencies as happening because of magic.
- Voodoo Shark: An attempt at fixing a Plot Hole that only results in making an even bigger Plot Hole.