Ghostbusters is a 1984 American supernatural comedy film, directed and produced by Ivan Reitman and written by Dan Aykroyd and Harold Ramis. The film stars Bill Murray, Aykroyd, and Ramis as three eccentric parapsychologists in New York City who start a ghost-catching business. Sigourney Weaver and Rick Moranis co-star as a client and her neighbor. The Ghostbusters business booms after initial skepticism, eventually requiring a fourth Ghostbuster, played by Ernie Hudson; but, when an uptown high-rise apartment building becomes the focal point of spirit activity linked to the ancient god Gozer, it threatens to overwhelm the team and the entire world.