I had decided to go to theatre with my friend. The tickets were already bought. However, I needed to work later that night, and I knew that I would be late for the theatre. I called there and asked for advice. We made up with the porter that he would let me in without a fanfare half an hour belated. That is what we did. But just when I stepped in the theatre hall, a loud voice said: "Sorry I'm late". Everybody looked at me and wondered how I dared to disturb the play with such an apology! However, it soon became clear for everyone that the line belonged to the play and came from the stage.