Start your scene as late as possible and get out as early as possible. I’m sure you have read this before. Even heard it in a class. But what does it mean? How does it help your reader get involved in your story? How does it keep an audience wrapped up in your screenplay?
This construction of a scene creates structural tension. However, much you create tension among characters within a scene or sequence, the device of entering a scene as late as possible and leaving early creates tension for the viewer/reader.
You do not need to explain everything. This explaining/narrative is a common fault in scripts by beginning writers. Two people sit in a café talking about why they are there. No. Just start with the conversation.
This device is easier said than actually done. Starting late and leaving early does not necessarily mean that the scene is short or that it does not linger over an action.
If you are having trouble writing this way, try writing your entire scene. Then go back to find the very first action or sentence that absolutely cannot be left out to begin. Do the same at the end with to locate the very first action or dialog that can end the scene.
If you are struggling with this concept, as many writers do, I suggest watching films where the technique is used consistently:
(These films are available through Netflix and I’ve set up direct links.)
Watch each scene to notice where it begins and ends. What questions are asked? How are the questions answered later? Are the questions answered later? Notice the tension you feel at the end of a scene. Aim for that tension as you are writing.