It’s funny how ideas can get mixed up in popular culture.

I ran into a great example just the other day: you know how, in Austin Powers, at one point Dr. Evil’s chair goes haywire and he quips “I need a young priest and an old priest”?

This is, of course, a reference to the cast of The Exorcist - but a lot of folks didn’t catch it, having never seen the latter film. So they assumed he was desribing to a real (albeit obscure) exorcism ritual.

The description then got passed on to folks who’d never seen Austin Powers, either, and now there are a whole bunch of folks who think there really is a Roman Catholic exorcism ritual that specifically has to be performed by a young priest and an old priest. I’ve seen it turn up in ostensibly serious fiction.

All because of a one-liner joke that nobody got.