A plot hole, or plothole is an obvious mistake or missing element in the plot of a film, book or play. These include such things as illogical or impossible events, and statements or events that contradict earlier events in the storyline. Plot holes have been defined as "...contradictions in a screenplay...[which] can both be mentioned on paper or implied by the premise and universe of the screenplay."
While many stories have unanswered questions, unlikely events or chance occurrences, a plot hole is one that is essential to the story's outcome. Plot holes are usually seen as weaknesses or flaws in a story, and writers usually try to avoid them to make their stories seem as realistic as possible. However, certain genres (and some media) that require or allow suspension of disbelief—especially action, comedy, fantasy, and horror—are more tolerant of plot holes.
Writers can deal with plot holes in different ways, from completely rewriting the story, to having characters acknowledge illogical or unintelligent actions, to having characters make vague statements that could be used to deflect accusations of plot holes (e.g. "I've tried everything I can think of..." to keep critics from asking why a particular action was not taken). The nature of the plot hole and the developmental stage at which it is noticed usually determine the best course of action to take. For example, a motion picture that has already wrapped production would much more likely receive an added line of dialogue rather than an entire script rewrite. A voiceover done over footage from the film can also be used to resolve plot holes after production has wrapped.