 After being kicked out of their university, parapsychology professors Spengler, Stantz and Venkman decide to go into business for themselves by trapping and removing ghosts from haunted houses. After some initial skepticism, business is soon booming as The Ghost Busters rid New York of its undead. When a downtown skyscraper becomes the focal point of spirit activity linked to the ancient god Gozer, however, the problem may be more than the team can handle.