Ghostbusters was a supernatural comedy from 1984 starring Bill Murray (Venkman), Dan Aykroyd (Stantz) and Harold Ramis (Spengler). The film is about three parapsychologists who set up a business in New York to catch ghosts in a similar manner to pest controllers. After successfully catching and containing their first ghosts, the team become minor celebrities and are hired to clean up the city from the ever-increasing number of ghosts, eventually hiring a fourth Ghostbuster, Winston (Ernie Hudson), to assist them in their endeavours.
Everything seems to be going pretty well until the Ghostbusters are called to investigate a demonic spirit called Zuul who, rather bizarrely, seems to be living in Sigourney Weaver’s fridge. It turns out that the fridge is actually a portal to a spiritual realm where the demigod Gozer the Gozerian lives who just happens to be planning a visit to New York to bring about the end of the world.
As the Ghostbusters plan their strategy for preventing the appearance of Gozer and saving the world, a visit from the US Environmental Protection Agency leads to the Ghostbusters’ facilities being shut down because of the suspected use of dangerous chemicals. This unfortunate glitch in the plans results in the ghost containment machine being deactivated which then releases all the captured ghosts back into the city, causing mayhem and ending with the mayor asking the Ghostbusters to resume their activities.
Whilst the Ghostbusters attempt to recapture the freed ghosts, they are unable to prevent the appearance of Gozer who takes the form of whatever the Ghostbusters imagine it to be. Unable to keep his mind blank, Stantz tries to think of “something that could never, ever possibly destroy us” whereupon Gozer emerges in Stantz’s chosen form of the, now iconic, giant Stay Puft Marshmallow Man! The giant Marshmallow Man then begins destroying the city but is eventually stopped by the Ghostbusters who dangerously cross the energy streams of their backpacks in order to blow him up.