The scene that begins when Ty Webb's golf ball crashes into Carl Spackler's shack was not in the original script. It was added by director Harold Ramis after realizing that two of his biggest stars, Chevy Chase and Bill Murray (who previously did not get along due to a feud dating back to their days on "Saturday Night Live", but were at least tolerant and professional towards each other while on set), until then, did not appear in a scene together. The three met for lunch and wrote the scene. This is the only film that Chase and Murray have appeared in together.