content of a book, play, musical work, film, video game, or television series which is not announced explicitly by the characters (or author) but is implicit or becomes something understood by the observer of the work as the production unfolds. It is content underneath the spoken dialogue. Under dialogue, there can be conflict, anger, competition, pride, showing off, or other implicit ideas and emotions. It is the unspoken thoughts and motives of characters—what they really think and believe.
"reading between the lines" See "iceberg theory" in Wikipedia
Example: In "Hills," The American clearly wants the girls to have an abortion but continually says he does not want her to do anything she doesn't want to do.