Screenwriting 101 -- David Mamet

"Theoretically, perfectly, what one wants to do is put the protagonist and the audience in exactly the same position. The main question in drama, the way I was taught, is always, What does the protagonist want? That's what drama is. It comes down to that. It's not about theme, it's not about ideas, it's not about setting, but what the protagonist wants. What gives rise to the drama, what is the precipitating event, and how, at the end of the play, do we see that event culminated? Do we see the protagonists wish fulfilled or absolutely frustrated? That's the structure of drama. You break it down into three acts." -- David Mamet (The Untouchables, Glengarry Glen Ross, The Spanish Prisoner)