The headmaster of the high school was a raging alcoholic. Frequently in the evenings, especially on a Friday and on weekends, he would be seen on the street by students of the school. He would be clutching a paper bag with a bottle inside, and be saying “How do you do?” to anyone who passed by.
Things were getting serious. A group of parents decided to confront him. He accepted what they said. He said he would admit to his problem and join an Alcoholics Anonymous program. To help him face it, he wanted to speak to the oldest students of the school, admit to his alcoholism, and ask for their support.
The students gathered. The headmaster entered the room. There was a faint smell of gin. He announced to the students that he was going away for a while. He explained why. He asked for their support. It was very moving.
The headmaster then went to leave and walked slap-bang into the closed exit door. The students laughed. All was ruined.