You can't think of Ghostbusters without thinking of the classic character known as Slimer - the gross, green ghost that the boys stumble across in a New York City hotel.
The film was made in 1984 and was pretty bold in terms of its special effects.
But while audiences in the 80s were bowled over by the final product, the team that produced the floating slime ball were stressed AF putting it together.
Special effects wizard Steve Johnson has revealed that Slimer was the product of a cocaine-fuelled bender when producers said they wanted it to look like John Belushi because actors Harold Ramis and Dan Ackroyd were mates of his.
"I was three grams into the night and in a cocaine-induced delusional paranoia and I literally thought that John Belushi's ghost came to me to help me out," he wrote in his upcoming book RUBBERHEAD Volume II: Sex, Drugs, and Special FX.
He said that he had been working on Slimer for six months and not once did they tell him about their desires for a green, ghost version of Belushi.
Johnson said that creating Slimer was hell.
Revealing in his first Rubberhead book, he wrote: "That was the most annoying horrendous experience I've ever had working with art directors, producers, and directors, ever.
"In the beginning they asked for a 'smile with arms' but before I knew it, it was a goddamn bleeding nightmare... 'Give him 13 percent more pathos, put ears on him, take his ears off, less pathos, more pathos, make his nose bigger, now his nose is too big, make his nose smaller...' Are you kidding? 'Make him more cartoony, make him less cartoony'.
"I almost fucking severed my own head during that process."
Johnson's work on Slimer really helped launch his career and he's since gone on to work with the likes of Michael Jackson, James Cameron, Guillermo del Toro and Tim Burton.
But while the green ghost was a raging success, he's certainly not suggesting anyone with a creative block to call up a dealer and bust through a bunch of cocaine.
"I'm not glamorising anything," he told Entertainment Weekly. "I'm basically screaming to the universe, 'Look, here's what happened to me, don't make these same mistakes'."
In addition to creating Slimer, he's also been responsible for Sil in Species, Doc Ock in Spider-Man 2 and Robin Williams' robotics for Bicentennial Man.
Featured Image Credit: Columbia Pictures