Way back in the 80’s a neighbor of ours was house manager for a theater, and I’d occasionally work as an usher there with her son. Rodney Dangerfield came through town for a few shows and I was lucky enough to work them. To make a long story short, the first performance was awesome, and he had snappy comebacks when he was heckled. But at the second performance it was clear somebody was feeding him lines, because he was heckled the same way at the same time in his act. From the back of the theater we actually spotted the guy who was doing it since he was slowly walking around the back.

Also, that second night a real heckler yelled out something at Rodney as well. Rodney paused briefly then continued on with his routine like nothing had happened.