Creating the Character's Emotional Arc: The Heart of the Story
Dialogue needs to accomplish one of three things: give information, move the story forward, reveal character. If the dialogue doesn't fit into any of these categories, don't use it. Don't slow down the screenplay by writing dialogue that is filled with directions. The biggest mistake beginning screenwriters make is having the characters give long-winded speeches that end up sounding like monologues. Use short speeches and crisp dialogue. Silence can be more impactful and emotional than extensive dialogue and explanations. In addition to all the dialogue sounding the same, the common problem with dialogue is there seems to be no differentiation between each character's styles of speech. Dialogue should create emotional conflict between the characters and develop tension between them that leads to some new action being taken on the part of the characters. Exposition is the act of writing necessary information to the audience, so they can understand the purpose of the story.