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Film 899: Ghostbusters

Trivia: The role of Louis Tully was originally written for John Candy.

The role of Peter Venkman was originally written for John Belushi.

According to Ivan Reitman and Harold Ramis in the DVD Commentary, in Dan Aykroyd's original rough draft of the movie, the story was going to take place in the future and that there would be teams of Ghostbusters like there are paramedics and firefighters (thus explaining basing the Ghostbusters HQ in a firehouse). According to Reitman, such a film would cost "at least $300 million in 1984 dollars". So Harold Ramis was brought in to rewrite the script and bring it into modern times.

Gozer was originally going to be played by Paul Reubens, who turned down the role. In the original script, Gozer took on the form of Ivo Shandor (the ghost building's architect, who started the original Gozer cult), who resembled a pale, slender, unremarkable man in a business suit.

When Venkman mentions the time Spengler tried to drill a hole in his head, Spengler's response ("That would have worked if you hadn't stopped me") was actually ad-libbed by Harold Ramis.

Bill Murray agreed to do this movie only on the condition that Columbia finance a remake of The Razor's Edge with him as the star. The remake was made (The Razor's Edge).

The party scene where Louis Tully (Rick Moranis) mingles with his party guests (commenting on the price of the salmon, and so on) is not only taken in one continuous shot, but is almost entirely improvised.

The movie's line "Dogs and cats living together! Mass hysteria!" was voted as the #68 of "The 100 Greatest Movie Lines" by Premiere in 2007.

Christopher Walken, John Lithgow, Christopher Lloyd and Jeff Goldblum were all considered for the role of Dr. Egon Spengler.