Dan Aykroyd first devised the concept behind 'Ghostbusters' in the early 80s with the intent of accomplishing two very holistic tasks. Firstly, he created this project so he could use it as another vehicle to team-up with his usual 'Saturday Night Live' / 'Blues Brothers' co-star / friend, John Belushi. And secondly, the basic idea behind this story was inspired by his love of the paranormal, a story which basically saw a group of "Ghostsmashers" travelling through time, space, and other dimensions, zapping huge ghosts along the way.
Another source of inspiration for Dan came in the form of two movies which were released in the late thirties and the mid forties. The first one was the 1946 Bowery Boys slapstick comedy, 'Spook Busters', where as the second one was the 1937 Disney short, 'Lonesome Ghosts', which funnily enough, included the famous line, "I ain't scared of no ghost".
However, all of that changed when John Belushi tragically died of a drug overdose on the 5th of March, 1982. Not only did it force Dan to re-write the script and tailor it for John's eventual replacement, Bill Murray, but on top of that, Ivan Reitman, who was assigned to produce and direct, liked the basic idea behind it yet also frowned at the financial impracticality of Dan's first draft. So at his suggestion, both Dan and Harold 'Egon' Ramis got together and overhauled the script; giving it it's now memorable tone.
On a side note, Ivan and Harold worked as director and co-writer respectively on the 1978 dorm-room comedy, 'National Lampoon's Animal House', which coincidentally starred Belushi as Bluto, yet passed up on Dan to play D-Day.
Now while I'm on the topic of casting, during the casting stage the script got yet another overhaul because John Candy, who was supposed to play a 'Ghostbuster' in the film, dropped out of the project, even though he could have opted for the lesser role of Louis Tully, a role which would eventually go to Rick Morranis.
Another snag at the casting and re-writing stage came when Eddie Murphy was going to play one of the gang. Initially he was hired to play the character Winston and have a back-story that involved him being an Air Force demolitions expert. But when he dropped out --- allegedly, due to creative differences -- so too did Winston's back-story, despite Ernie Hudson quickly putting on Eddie's Proton-pack, so to speak.
Thankfully, once all of the snags where ironed out and the film was finally shot, POW!, 'Ghostbusters' went on to become one of the most memorable ghost inspired comedies ever made. So much so in fact, that it's sequel took a bashing in the press because it kept on getting compared to the original, and now, now the remake is here, well, no one likes the trailer, so what chance has the film got? Not much, eh?
Personally, I like Kristen Wiig and some of her 'Bridesmaids' cohorts so I'd watch it for that alone, regardless of it's connection to an 80s classic. Granted, I don't think it's going to be as memorable as the original. But then again, after knowing what I know about the original, the original wasn't the original we all thought it once was. Know what I mean?