The TV Writer on TV Writing
by Larry Brody
Scenes are more than signposts on your way to the end of the screenplay road. They’re more than just moments in which story or character points are thrown out at the viewer or reader. A good scene in a screen or teleplay — and by good I mean EFFECTIVE in terms of getting the response you want — is a mini-film in itself, with a beginning, middle, and end.
Scenes need to be structured so that their intensity grows and then climaxes, like microcosms of your script. (And, I think it’s clear, sex too – but we’re not going there right now.)
This doesn’t mean that a scene should go on and on. far from it.