Terry Rossio once said that the most powerful words in the history of cinema were "He fought with your father in the Clone Wars." In those nine words, Darth Vader gains a background, Luke gains a father, and the universe gains a history, all of which are lyrical and evocative. One needn't know anything about the father or the Clone Wars - they just were, and even though no information is contained in the sentence that is relevant to the plot or characters, they enrich every aspect of the film from that point forth.

His writing partner, Ted Elliott, once related to me a tale about JRR Tolkien. Someone wrote him asking what was beyond the "Distant mountains of Mordor." He wrote back saying something along the lines of "Milady, were I to tell you what lies beyond the distant mountains of Mordor, you would ask what lies beyond that, and beyond that, and beyond that, and so on. Suffice it to know that I know what lies beyond the distant mountains of Mordor and that if you need to know, I will tell you."

Something few writers (and fewer non-writers) know is that it's not the story you tell, it's the story you don't tell. Whitespace has its value in all things.