"depends on what's caught in the zipper..."

A long time ago, a girlfriend's dad told me about an incident in the thirties when he went into a movie to kill time waiting for a meeting to start.
He was the first person to enter. The second was a fat man who unzipped his trousers because they were too tight when he sat down.
As the theatre began to fill up, a woman tried to pass in front of the fat man. He had to get up to let her past him, and as he did so, his trousers started to fall down. He tried to zip up, but got the rear of her skirt caught in the zipper. The woman, thinking he was assaulting her sexually, began to scream. It was a very long minute before an usher with a flashlight was able to solve the problem.