Doctors Peter Venkman, Raymond “Ray” Stantz and Egon Spengler, three researchers from Columbia University in New York, specialize in parapsychology. Accused of carrying out crazy research, they are finally removed from their position by the dean of the university.

The trio decides to open a paranormal investigation company, which they name “Ghostbusters”. Committing their last funds to this activity, they bought an old abandoned New York fire station, which they renovated and modified. They hired Janine Melnitz as their secretary and developed high-tech nuclear equipment to capture and contain the ghosts and their Ectomobile "Ecto 1", a white Cadillac decorated with their company motif, although business was initially slow. .