Don't Think Twice (2016)

This movie is on and about the art of improvisation.  Before the story gets going, there is a brief introduction to the history of improv, as well as an explanation of the cardinal rule of improv, which is commonly known as "Yes, and ... ," this means that a performer says "yes" to everything that happens on-stage. One of the cardinal sins of improv is saying "No." 
The movie follows a New York-based improv group through a year in their lives. The Brooklyn theater where they've been performing has been sold, and homelessness approaches.  One of their members makes it big and the others try to ride his coat tails, which puts him in awkward situations.  The competition to make it is inconsistent with the desire to create scenes that are made up of teamwork.  We get an up close and intimate look at the inner workings of this art form.  Really good and it grows on you after you finish.