If you want to see what works in a short play, be part of a short play festival and watch your fellow entrants (or sit in the lobby listening) over and over. By the end of the run, you’ll know.
I had the good fortune a few years ago to have a piece in a Christmas monologue event sponsored by my then-group Playwrights 6. I was at the theatre every night because I was helping set up or selling tickets etc. All of the pieces were stage-worthy… but the one I made sure to catch every night was by Gib Wallis. His character, a charming and gregarious immigrant named Alfredo, relives his first Christmas in the U.S. and his first-time meeting a guy under the mistletoe, told in fractured English. My heart never got tired of going on that journey with him.
A couple of weeks ago I had a short play in a weekend of shorts sponsored by my current writers’ group Fierce Backbone, and this time the piece that grabbed me was Ten Hours by David Watkins. In brief scenes it told the ten hour journey of a man and woman meeting, getting to know each other over some meals and in bed… And then it ended in a heart-breaking moment of the man saying to the woman, when pressed why he doesn’t want to date her, “You’re fat.” I knew how it ended and yet I got pulled in every time.
Neither of these short plays were clever or flashy. Both of them allowed their characters to be vulnerable, to let me see inside their hearts. My favorite type of theatre.