Originally conceived by Aykroyd as a futuristic, interdimensional adventure titled Ghost Smashers , the script was heavily revised by Ramis and Reitman to make it affordable and relatable.
: The protagonists are expelled from the "ivory tower" of Columbia University, only to find that their "useless" research is the only thing capable of saving the city.
At its core, Ghostbusters is a satire of institutional pomposity .
: The film shifts the focus from space travel to three disgraced parapsychologists—Venkman, Stantz, and Spengler—starting a small business in an abandoned firehouse .