Masters of dialogue compel the reader to keep reading, pulling the truth just out of their reach, like a carrot on a stick. Then surprise the reader: the carrot turns into a pickle. In other words, engaging dialogue that leaves us questioning creates expectations. And that creates suspense.
When characters always speak their mind exactly, whether through internal or external dialogue, that’s called “on the nose” dialogue. And it’s dull. Predictable even. Not suspenseful.
As Robert McKee says in his screenwriting book, Story, “The text cannot be about what the text is about.”
Subtext is the path of most resistance. This is dialogue that refuses to spill the beans, keeps your reader guessing as to what’s actually being said, keeps them engaged. When done well, it’s secretive, but sexy.
When characters are not saying what they really mean, but their words allude to something altogether different, that’s subtext. Like saying “Lovely day” to your boss, who terrifies you, when what you really mean is “Please don’t fire me.” Subtext is the meaning behind the message. The code that your reader has to break to feel not just engaged, but included in the story.
Two characters may not ever say they are in love with each other. That would be too direct, too everyday. Too dull. And cliché, frankly. It’s been said over and over and over… Instead, they may converse in code. Examples:
1) In the Princess Bride, the farm boy, Westley, says to Princess Buttercup “As you wish” to say "I love you." This the code that he later speaks to reveal his identity, for she’d thought he’d been killed years earlier.
2) Likewise, Lauren Bacall’s character, Marie, in To Have and Have Not, tells Humphrey Bogart’s character, Harry, “You know how to whistle, don’t you? Just put your two lips together and blow.”
Can you guess what she’s talking about? This, of course, was in a heavily-censored movie era, when the explicit discussion of sex was not allowed. And why change that? Talking explicitly about sex is almost always less interesting to a reader (excepting erotica, of course).
Subtext is about carefully crafted subtlety, and that’s just sexy.