Here's what happens in a play. You get involved in a situation where something is unbalanced. If nothing's unbalanced, there's no reason to have a play. If Hamlet comes home from school, and his dad's not dead and asks him if he's had a good time, it's boring. But if something's unbalanced, it must be returned to order.
David MametConsider: for all the gobbledegook [film studio] executives spout about backstory, all that we, the audience, want to know is what happens next. That's the only thing that's going on. . . . Character is nothing other than action, and character-driven means The plot stinks, and you'd better hope the star is popular enough to open the movie in spite of it.
David Mamet