According to Wikipedia, a beat is the moment in a scene at which increasing dramatic tension produces a noticeable change in the consciousness of one or more characters. An event, a decision, a pivot.
Someone suggested Big Little Lies as a good lockdown watch. I remembered to breathe and then remembered turning the page to the first tellings of domestic abuse in that book when I read it years ago. It made me shake and cry. I didn’t see it coming. I’d bought in completely to the perfect smiling family, because it must be so, because look at the pictures on their wall.