The Ghostbusters franchise consists of American supernatural comedies, based on an original concept created by Dan Aykroyd and Harold Ramis in 1984. The plot follows a group of eccentric New York City parapsychologists who investigate and eliminate ghosts, paranormal manifestations, demigods, and demons. The franchise expanded with licensed action figures, books, comics, video games, television series, theme park attractions, and other branded merchandise. Bill Murray, Dan Aykroyd, Ernie Hudson and Annie Potts are the only actors to have appeared in all five films in the Ghostbusters franchise.