Chevy Chase and Michael Keaton both turned down the role of Dr. Peter Venkman.
The 555 phone number from the commercial was an actual, working number with a recording of Raymond and Venkman. The number got 1,000 calls an hour, 24 hours a day, for 6 weeks before it was shut down.
The Marshmallow Man suits cost $20,000 each to make. Three were used and destroyed during filming.
The marshmallow goo that explodes on Atherton was actually 50 pounds of shaving cream.
Porn star Ron Jeremy appeared as an extra in the film, and later starred in a porn parody called This Ain’t Ghosbusters XXX.
Ray Parker Jr.’s Ghostbusters theme song was a Number 1 hit for three weeks.
The film made $240 million domestically in 1984.
The jail scene was filmed in a real prison, with many of the cast and crew believing the building was actually haunted.
The firehouse headquarters was remodeled as the mechanic shop in The Mask.
It’s located at 14 N. Moore St., Manhattan, New York.
Dan Aykroyd originally wrote the script to take place in the future, but Harold Ramis rewrote it to take place in current times.
Due to the time change in the script, the production budget was cut from a projected $300 million to a little over $30 million.
Bill Murray’s role, Dr. Peter Venkman, was originally written for John Belushi but he died while the script was being written.
On set, Dan Aykroyd called Slimer “the ghost of John Belushi.”
The Ecto-1 is a 1959 Cadillac Miller-Meteor ambulance limo that was transformed by Universal studios.
Ghostbusters was the highest-grossing comedy of all time. The film would keep this title until the release of Home Alone.
There was actually a second version of the Librarian Puppet, but it wasn’t used because it looked too disgusting.
However, it was later used in Fright Night a year later.
Two of the main roles were developed with Eddie Murphy and John Candy in mind. Murphy was to paly the role of Winston Zeddemore, but due to a clash filming Beverly Hills Cop, he turned down the role.
John Candy was in discussions to play Louis Tully, but declined the role after delays in production.
The party scene with Rick Moranis was almost entirely improvised.
Bill Murray agreed to his role in Ghostbusters with the stipulation that the studio remake The Razor’s Edge with him as the star.
The cast and crew called the Slimer prop “onion head” because of how bad it smelled.
The term “proton pack” wasn’t actually used until the middle of Ghostbusters II.
The guns used for the proton packs were originally supposed to be wands. They were changed to laser guns to make it more believable that the team created their gear from random equipment.
Ghostbusters was Larry King’s film debut.
To show how massive the Stay-Puft Marshmallow man was, the monster was originally supposed to come out of the water next to the Statue of Liberty.
The creepy, demonic voice of Zuul was performed by director Ivan Reitman.
Most of Bill Murray’s lines were ad-libs.
The film was originally titled Ghost Smashers, but director Ivan Reitman wasn’t a fan.