Watch a stage play and the story is told mainly through dialogue with physical action secondary. Then watch a movie and the story is told mostly visually through action with dialogue secondary. So if you want to write a screenplay, focus first on action and dialogue second.
Showing two people talking (known as “talking heads”) visually looks dull so screenwriters often rely on several tricks to spice up the scene. The most common trick is to use the setting to enhance or interfere with the scene.
In “Blood Simple,” two people talk but inside a strip club. So as they talk, we can see the legs of a stripper as her clothes drop down around her legs. The strip club has nothing to do with what the characters are talking about, but it adds a visual element to the talking heads scene and adds to the setting of the overall story as a fairly seedy, low class world.
In “Rocky,” Rocky and Adrian are in a skating rink by themselves. Not only are they talking, but they’re also skating awkwardly because Rocky paid the janitor to let them skate for a few minutes after hours while the janitor keeps calling out how much time they have left.
This scene helps highlight the awkwardness of Rocky and Adrian getting to know each other, but was also a cost-cutting measure because an empty skating rink was cheaper to rent out without extras, which was their original plan.
So when writing any scene, also look at it from the point of view of cost. Was it necessary to hire dozens of extras to skate around Rocky and Adrian? Not really, so not only does the vast emptiness of the skating rink highlight the main characters better, but it also proved cheaper on the budget as well.
First, write your scene as pure action as if it were a silent movie. Second, add physical action for the characters to perform because body language can tell a lot. Third, choose a setting that highlights or interferes with the characters.
Action, dialogue, setting. Those are the three keys to help make a scene as fully dimensional as possible. Read any scene that lacks these three elements and you’ll find that the scene is either flat and dull, or not fully realized.
Finally, add a fourth element by planting seeds for the future. A scene is not an isolated story in itself, but a promise of something bigger in the future. When a scene is both interesting in itself and promises something in the future, then it’s likely a strong scene that moves your story forward.