If I'm remembering correctly, there's such a scene in Hitchcock's "Stage
Fright" which has garnered much attention. And perhaps to less an extent,
"Despair" (Fassbinder) has such scenes, but the line between reality and
fiction is pretty shaky throughout. By the way, is the scene you're talking
about in the recent movie located in a bar? Wondering if I know which movie
you're talking about.