Married to writer John Emerson, the pair wrote one of the first books on screenwriting in 1920: “How to Write Photoplays”. I have been running a weekly series based on the book. You can access those posts here. Today: Midway in the Photoplay [P. 101]:
When you are at a loss to carry on the action, cut over to the parallel line of action which is taking place in the next street or the next town; leave your repentant thief to show the detectives preparing to nab him, and so forth.
As noted the last few weeks, what Loos and Emerson are talking about here is what has come to be known as a subplot, a secondary or “minor” plot. And specifically here, they refer to an editorial technique commonly referred to nowadays as a cross-cut.
This is one of the most valuable assets of a subplot: to “cut over to [a] parallel line of action.” Through various subplot intersections, it allows you to reveal different thematic aspects of the narrative. Plus each transition offers you an opportunity for an interesting and entertaining moment, the conjunction of two storylines offering a range of narrative possibilities ranging from similarity to contrast.
In terms of action sequences, cross-cutting between parallel lines of action is a great way to ratchet up the energy. Track each cut in the assault on the Death Star from Star Wars: Episode IV — A New Hope:
Whether you use cross-cuts in concurrent time to create a kinetic action sequence or bounce from one storyline to another, your awareness and use of parallel lines of action is one of the most useful tools in a screenwriter’s toolbox.
Next week: More on subplots from Anita Loos and John Emerson’s book from 1920.
If you live in the U.S., you can read “How to Write Photoplays” via Google books online here.