Many a writing paradigm decrees that revealing plot via dialog is a cardinal sin. Nothing makes your characters sound more contrived than leading questions and answers obviously positioned to reveal stuff to the reader. And yet, you can't fill a book with characters speaking in a rhetorical fog. Something has to happen within discourse, right?
Yes and no.
Voice, personality, cadence, narrative texture: these are the take-aways when your characters chat it up on the page. It's about connective tissue. The substance that makes it possible for the reader to align with--to move with--the story.
Right now I've got seven characters in a kitchen. They have to talk, or not talk. They need to gesture, to fill the voids with physical business. The chasms between what they do and what they say can provide irony that moves the storyline forward. In these moments of irony, we can find out some things.
Dialog can be used the way emjambment is used in poetry: to subvert or heighten expectation, and thus create tension, or interest. You want to use dialog to open doors, rather than close them. You want the reader to glimpse a room she didn't know existed in the house she's exploring rather than providing the entire floorplan.
So. My seven odd characters are in a room, and within the course of this association, there needs to be a reveal. But it can't come from an answered question. Instead, it has to arrive via an unanswered question. That's today's challenge.