Brian Doyle-Murray, who co-wrote "Caddyshack" and played caddy manager Lou Loomis in the film, said he had no idea how assistant superintendent Carl Spackler would look or sound.
Doyle-Murray said he knew his brother Bill was the man for the job because they had both caddied at Indian Hill Golf Club in Winnetka.
"That great side-talking, imbalanced greenskeeper came out of nowhere," said Doyle-Murray. "In the original scripts it would say, 'Bill will ad-lib. Chevy and Bill will ad-lib.' That's all it said, those scenes with the guns and gophers and stuff, it came from Billy's head.'"