When is a macguffin not a macguffin?

At what point in a movie is it too late to call something a macguffin? I'm thinking about the scene in Small Town Murder Songs when the huge double-wide is hauled through town escorted by the police while sacred harp singers sing a song called Antioch. I love that part and watch it sometimes just for the power the music lends to the scene. But, at that point, we are well into things, and it seems to have no relevance to the remainder of the movie. Or, if you like, what are good examples of other great great macguffins?

I'd say no. To be a macguffin it has to set major plot develops in motion.

a macguffin?

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Officialadamn

Couldn't it be used simply to drive the plot forward and not just to set major events in motion?

I think I agree with Yoda here. When I here MacGuffin I immediately think of Pulp Fiction's Briefcase and North by Northwest's microfilm.

I'm not entirely sure a distinction can be made between "drive the plot forward" and "set major events in motion." Major is a relative term, so anything driving the plot forward is automatically a "major event" in that context, I would think.

I think a MacGuffin should link the film, like be constant and always important to the scene that is occurring, linking together the story and acting as a way of connecting the narrative. It's basically an excuse for a story to exist.

An example of it setting up the story but not being used all the way through, is in Skyfall, it gives a recent for Bardem's character to exist (the thing with a list of agents names) but once he has been introduced it's no longer needed.

Unobtanium in Avatar... is an example of all types.


It's the reason humans are on Pandora, the reason for the film being able to take place at all... yet for all its importance, it has nothing to do with the basic story and is only mentioned during the first 10 minutes, then once again a little while later when they're talking about Hometree.
Other than that, it's never mentioned.

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Found this on Wiki...

In fiction

So a MacGuffin can be all sorts of things, usually an object but not always... and doesn't have to be important to the plot.

The black bird in The Maltese Falcon, the stolen money in Psycho, the ark in Raiders of the Lost Ark are among my faves.

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Definitions seem to abound in a wide variety, but I like the above example very much. In my example, then, the scene serves no purpose at all. Still, the music and the police escorted double-wide captivate my attention and leave me spell-bound until the next scene - which may have been the idea in the first place.