Bill Murray and Sigourney Weaver in Ghostbusters (1984)

Bill Murray and Robin Williams in Ghostbusters (1984)

Sigourney Weaver and Steve Johnson in Ghostbusters (1984)

Dan Aykroyd, Bill Murray, and Harold Ramis in Ghostbusters (1984)

Dan Aykroyd and Annie Potts in Ghostbusters (1984)

Dan Aykroyd, Bill Murray, Harold Ramis, and Ernie Hudson in Ghostbusters (1984)

Dan Aykroyd and Bill Murray in Ghostbusters (1984)

Dan Aykroyd, Bill Murray, Harold Ramis, and Ruth Oliver in Ghostbusters (1984)

Sigourney Weaver and Rick Moranis in Ghostbusters (1984)

Dan Aykroyd and Ernie Hudson in Ghostbusters (1984)

Ivan Reitman at an event for Ghostbusters (1984)

Ivan Reitman at an event for National Lampoon's Animal House (1978)

Dan Aykroyd, Bill Murray, Harold Ramis, Ernie Hudson, Ivan Reitman, and Mark Bryan Wilson in Ghostbusters (1984)