A plot device that motivates the characters and advance the story, particularly one whose importance is accepted completely by the story's characters, yet from the audience's
perspective it might be minimally explained or may test their suspension of disbelief if it is scrutinized. The device, usually an object, is common in films, especially thrillers.
It is important that the audience never actually see the MacGuffin. I dunno why.
The term "MacGuffin" was invented by Alfred Hitchcock; according to the Oxford
English Dictionary, he explained the term in a 1939 lecture at Columbia University:
In regard to the tune, 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 always the necklace and in spy stories it is always the papers.
Interviewed in 1966 by François Truffaut, Hitchcock
illustrated the term "MacGuffin" with this story:
It might be a Scottish name, taken from a story about two men in a train. One man says, 'What's that package up there in the baggage rack?' And the other answers, 'Oh that's a McGuffin.' The first one asks 'What's a McGuffin?' 'Well'
the other man says, 'It's an apparatus for trapping lions in the Scottish Highlands.' The first man says, 'But there are no lions in the Scottish Highlands,' and the other one answers 'Well, then that's no McGuffin!' So you see, a McGuffin is
nothing at all.
