No matter what your screenplay is about, or what genre it is, it really comes down to one thing: telling a story about the characters and what happens to them.
While some may put more emphasis on the latter part with its vast number of variables and possibilities, it’s equally important to put a lot of effort into developing the former.
You want your characters to be relatable. Let us see ourselves, or at least part of ourselves, in them. How they act and interact. What they do. Even if it’s within a completely ridiculous or unbelievable scenario.
A good example: the works of Judd Apatow. “Comedies with heart,” is often used to describe them. By injecting emotion into what might otherwise be just something silly, he adds that extra layer of humanity. Notice you never heard the phrase “wacky hijinks ensue”? Because it’s about the emotion within the comedy, not just going for the cheap laugh.
Nobody only experiences one emotion, and neither should the fictional population within your pages. If a character’s happy, sad, or angry, show us why. Don’t hold back. Put it there for us to see.
Do they act like a real person? Is this how they would act in this kind of situation? Is it a real reaction or a “movie” reaction? Getting your characters to act using their emotions makes them come across as more realistic, which makes for a better story.
“The characters are too one-dimensional,” or “He/She’s just a one-note character.” Heard those before? If your character only acts one way, or remains static and never changes, or doesn’t even react accordingly, that’s what the response will most likely be. And you don’t want that.
A savvy writer knows how to use emotion without being blatant about it. Maybe it’s a subtle action, or a turn of phrase, or the subtext within a line of dialogue.
Find the way that works best to develop and advance the character both within their own story and the story overall.