In fiction, a MacGuffin (sometimes McGuffin or maguffin) is a plot device in the form of some goal, desired object, or other motivator that the protagonist (and sometimes the antagonist) is willing to do and sacrifice almost anything to pursue, often with little or no narrative explanation as to why it is considered so desirable. A MacGuffin, therefore, functions merely as "a plot element that catches the viewers' attention or drives the plot of a work of fiction". In fact, the specific nature of the MacGuffin may be ambiguous, undefined, generic, left open to interpretation or otherwise completely unimportant to the plot. Common examples are money, victory, glory, survival, a source of power, a potential threat, a mysterious but highly desired item or object, or simply something that is entirely unexplained.
The MacGuffin is common in films, especially thrillers. Usually the MacGuffin is the central focus of the film in the first act, and then declines in importance as the struggles and motivations of characters play out. It may come back into play at the climax of the story, but sometimes the MacGuffin is actually forgotten by the end of the story. Multiple MacGuffins are sometimes—somewhat derisively—referred to as plot coupons.
The term is also used by a game development studio as a reference to a design object which forces interactivity on to a narrative.
Read more about MacGuffin: History and Use, Filmmakers’ Jokes, Examples, A Different View