After getting into the old-age makeup,
John Dugan decided that he did not ever want to go through the process again, meaning that all the scenes with him had to be filmed in the same session before he could take the makeup off. This took about 36 hours, during a heat wave where the average temperature was over 100 degrees, with a large portion of it spent filming the dinner scene, sitting in a room filled with dead animals and rotting food.
Edwin Neal who played the hitch-hiker claimed "Filming that scene was the worst time of my life... and I had been in Vietnam, with people trying to kill me, so I guess that shows how bad it was."
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