I did. I rushed at the man. 'Stop it,' I shouted. He let go of the boy and with his arms extended ran after me. Somehow I got away and hid behind John, cowering. I am just a little over five feet tall and weigh a hundred pounds. John is a large tall man. (Both of us were in our sixties.) I peeked around him. The man was screaming, 'She can't talk to me that way.' His eyes popped out; he was red in the face, and kept waving his hands.
'And what do you think you are going to do?' John said in a low steady, almost nonchalant voice. I had my hand on his broad muscled back. The man went silent. He dropped his arms and walked away into the theater with the boy in front of him.
I followed but lost sight of them. When I told an attendant what had happened, she gave me a weak smile. There was nothing to be done. Of course, I should have called 911; I had my cell phone with me, but my impulses took over. At least John and I diverted the man, and he stopped beating the boy. Next time I'll have to think before I go up against a dangerous person. It won't do to act like a foolhardy pup if I'm going to try to help someone.
PS: after reading this post, John wanted me to include the race of the abuser: he was white. Does knowing his race and the race of the boy may a difference to the story?