The highest-grossing film of its time, Ghostbusters is the lovechild of Dan Aykroyd and Harold Ramis. Directed by Ivan Reitman, the 1984 film was nominated for three Golden Globes and received world-wide praise for its unique blend of slapstick humor and emotionally-driven storytelling. Featuring "ghosts like you've never seen," the film's lasting impression with its audience sparked interest in a sequel which was released in 1989. During its release, Ghostbusters 2 held the record for "the biggest three-day opening weekend gross" only to be broken a week later by Batman. Both films gave way to a franchise that spans spin-off television series, comic books, video games, theme park attractions and an all-female reboot in 2016 entitled Ghostbusters: Answer the Call.

The Ghostbusters legacy, lasting over 30 years, has remained steadfast due to its continual attraction of new fans and a dedicated cult-following still mesmerized by its cultural impact. Both the original films and the 2016 reboot have provided welcoming arms to anyone seeking to strap on a proton pack and save the world. After an agonizing wait, recent announcements have confirmed a third installment in the '80s franchise will be released next summer and possibly include returning members of the original cast. In the meantime, many "ghostbusters in-training" have devoted themselves to uncovering facts about the films and learning the grueling journey Dan Aykroyd and his crew took to have their vision see the light. Others have done their research and posed various theories and assumptions regarding the true nature of the Ghostbusters' otherworldly operations. In the end, after encountering spooks, specters, and ghosts, CBR asks "Who you gonna call?"

20 ALL IN THE FAMILY

Long before he strapped on his proton pack and began ghost-hunting, Dan Aykroyd was inspired by his own family's paranormal history when creating The Ghostbusters. His great-grandfather was a well-known 19th century psychic who held seances at the family's farmhouse in Ontario. Seeking to further communicate with the undead, his grandfather Maurice attempted to create a high-vibration crystal radio.

Inspired by his father's expansive collection of books about the supernatural and an article about parapsychology in a publication of the American Society of Psychical Research, Dan began writing the script for the film. Considering himself a devoted Spiritualist, Aykroyd went on to host Psi Factor: Chronicles of the Paranormal and aided his father's publication of History of Ghosts.

19 A MISSION FROM GOD

While writing the script, Dan envisioned a team comprised of himself, John Belushi, and (a rumored) Eddie Murphy. Belushi would've played the role of Peter Venkman before his untimely passing led to the part being taken over by Bill Murray. Best known for their antics as The Blues Brothers, Belushi and Aykroyd were close friend during their time on SNL.

Inspired by 1930s ghost films, especially the humorous Abbott and Costello movies, Aykroyd intended to make a screenplay explicitly written for "John and I." When Dan received word Belushi had passed from a drug overdose, he referred to the devastating news as "a Kennedy moment." Mourning the loss of someone he considered like a brother, Aykroyd paid clever homage to his fallen friend.

18 BECOMING A BOO BROTHER

Regarded as one of the most iconic creations from the beloved franchise, Slimer is said to be "the ghost of John Belushi." Originally referred to as "Onion Head Ghost," the green goon went through an intense series of revisions which almost led creator Steve Johnson to lose his mind. Constantly trying to make sense of the endless critiques he received from art directors and producers, Johnson was bombarded at the last minute by Aykroyd and fellow screenwriter Harold Ramis who sought to pay tribute to Belushi.

Locking himself away with headshots of the actor and some "mind-enhancing" substances, Johnson received "divine intervention" from what he truly believed was the spirit of the late comedian. The end result is the slime-tastic, always-hungry ghost fans have come to love.

17 CREATING A SPACE ODDITY

The all-powerful, androgynous entity Gozer was heavily influenced by none other than Ziggy Stardust himself, David Bowie. Wanting to honor the character's gender-fluidity, director Ivan Reitman suggested casting Grace Jones or Anne Carlisle for the role but by the time a final concept had been settled upon, it was too late to attach a big star to the role.

In one of the original concepts for the character, Gozer was going to take the form of her / their cult's leader Ivo Shandor who would've been played by Paul Reubens. Shandor is described as "a kindly-looking man" whose wardrobe consists of a "nondescript suit and tie," leading the Ghostbusters to easily dismiss him as a villain.

16 A STICKY SITUATION

Given the chance to choose the form of their ultimate destroyer, Ray accidentally envisions a "100-foot tall homicidal marshmallow man" who attempts to wreak havoc upon New York. Conceived as a combination of multiple friendly mascots, the entity known as the "Stay Puft Marshmallow Man" was originally designed as a "throw-away" character who wouldn't be introduced until halfway into the film. In was in the July 1983 draft of the script that the character would become the final villain the Ghostbusters would have to defeat.

Stay Puft's suit was built using pliable foam and given a fiber-glass skull which allowed for facial movements to be controlled through various mechanisms and cables. When the character is destroyed, over 100-pounds of shaving cream was used to create his gooey demise.

15 INVESTIGATING THE OTHER SIDE

Ghostbusters movie

Aykroyd's original script involved the Ghostbusters team fighting spirits in a dark, futuristic setting. Encompassing roughly 60-70 pages, the actor envisioned a multiverse where "competing teams of Ghostbusters" defeated ghosts across numerous timelines and dimensions. Reitman estimated that Aykroyd's vision, which included 50 life-size monsters, would cost over $300 million to produce.

Supported by Bill Murray and Harold Ramis, Reitman suggested his vision for the film to Aykroyd: a group of average guys interested in the paranormal get kicked out of their university and deicide to start a ghost-hunting business. Agreeing on this new idea, the team journeyed to Aykroyd's house and spent almost three weeks creating the final version of the film.

14 RIDING IN STYLE

Ecto-1's original concept including a sinister black paint-job featuring white and purple strobe lights to produce an eery glow. However, the directors found the vehicle hard to film during night scenes and decided to scrap the idea. The car also had the ability to dematerialize which would have been used during a police chase scene.

A fusion between a Miller-Meteor Futura Ambulance / Hearse Combination and a 1959 Cadillac Fleetwood Professional Chassis, the car came with unexpected problems. Originally estimated to only cost $600, by the time filming started, the price rose to $4800 (roughly over $1o-thousand in 2012 money). During filming for Ghostbusters 2, the car broke down on the Brooklyn Bridge causing the crew to be fined by the NYPD for causing a severe traffic jam.

13 A WASTE OF TALENT

Winston Zeddemore was originally intended to play a much more significant role in the film. In the August 1983 draft, he would've also been the most qualified member of the team with five years experience in the Air Force, possession of a 15th Degree Black Belt in Wing Chun Boxing, and being a well-trained weapons handler.

Realizing Winston needed to be the more responsible one of the group, the directors decided to scrap the idea of a comedian for the role having previously suggested Eddie Murphy and Gregory Hines. They decided to instead seek out an actor to "serve as the on-screen voice" of the audience who would offer a skeptical look at the Ghostbuster's supernatural shenanigans.

12 HAUNTED BY THE PAST

Ernie Hudson admits he still has mixed feelings when it comes to his role. Led to believe his character would be a founding member of the Ghostbusters, Hudson was shocked to receive a revised script that introduced Winston long after the team had been well-established. Having his impressive resume erased, Winston was reduced to accepting the job as a Ghostbuster for its steady paycheck.

Despite being described as "the Soul" of the group, Winston wasn't featured during the film's promotion and Hudson felt left out when it came to praising of the cast. Though adamant about not placing blame on the director or his fellow actors for lack of recognition, Hudson has expressed a desire to have played the original version of his character.

11 THE POSSESSION OF SIGOURNEY WEAVER

While Reitman originally wanted to cast Julia Roberts as Dana Barrett, actress Sigourney Weaver beat her out with a rather unusual audition. Seeking to delve into comedy, Weaver stated her character should become possessed by one of the Terror Dogs in the film and proceeded to get down on all fours and bark in front of the director.

Impressed with her commitment, Reitman immediately called Harold Ramis and began revising the rooftop scene to include Weaver's suggestion. Struggling to write a convincing love-interest who still maintained her independence, Ramis admits he heavily relied on Weaver's suggestions to add dignity to her character. Originally, Dana was an alien fugitive turned model before Weaver expressed her desire to have the character be a musician.

10 TRIBUTE OF TWINKIES

After his passing in February 2014, Harold Ramis was honored at the Hook and Ladder 8 firehouse which served as the headquarters for the Ghostbusters. Fans paid tribute to his character Egon Spengler by leaving Twinkies on a makeshift memorial in honor of the scene when his character uses the iconic Hostess treat to explain the increase in New York's supernatural activity.

In the 2016 reboot, Ramis makes a brief cameo toward the beginning of the film in the form of a bust located inside Columbia University. During the credits, a title card appears dedicating the film in his honor. Ramis' son Daniel also makes a brief cameo as a "Metal Head" during the heavy metal concert scene.

9 NOT SO FRIENDLY GHOST

The iconic "No-Ghost" logo each Ghostbusters member wears was designed by associate producer Michael C. Gross. However, in 1984, Harvey Cartoons launched a lawsuit against Ghostbusters claiming the design looked too similar to one of their characters. The company claimed the logo infringed on their copyright and trademark for "Fatso," a member of the Ghostly Trio from Casper, the Friendly Ghost.

Claiming the creation had the same "cleft chin, bulbous nose... and top-knotted forehead" as Fatso, Harvey Cartoons ultimately had their case dismissed by the courts who found the company had failed to renew their copyrights after the character's first appearance in 1950. Even without the protection, the court found the two images looked completely different.

8 SCARED TO DEATH

Recognizing the outrageous feat they had conquered, director Ivan Reitman was still terrified when it came to the film's first test-screening. Held at Columbia Pictures Studios three weeks after the crew had wrapped up principal photography, Reitman anxiously hid in the back of the theater to watch the audience's reaction to the only fully-completed special effects shot: the librarian ghost transforming into a scary ghoul.

Worried the audience would find the plot too childish and the additions of strange characters such as "Stay Puft" unneeded, Reitman was delighted to hear both howls of laugher and shrieks of terror during the screening. His fears were finally dismissed when during the film's second week of release, he witnessed several vendors selling bootleg t-shirts on the streets.

7 HELPING OR HURTING

No franchise is safe when it comes to conspiracy theories. The Ghostbusters films have managed to generate a lot of buzz on Reddit forums with devoted fans offering new insight into interpreting various scenes and plots. One popular theory posted on TinFoilFanTheories.com suggests the Ghostbusters team is actually doing more harm than good when it comes to their ghost-hunting activities.

The theorist suggests the team is "imprisoning" the ghosts simply because they are existing outside the spirit realm. While most contemporary ghost-hunters attempt to understand why the ghost still lingers, the Ghostbusters willingly trap the entities based on the assumption they are here to do us harm and leave them unable to journey to the afterlife.

6 WHO'S THE FATHER

Several theories posed by Ghostbusters' fans attempt to discover the identity of Oscar's father. In Ghostbusters 2, the audience is introduced to Dana Barrett's son  who becomes involved in the supernatural plot to become the host for a resurrected Vigo. Fans of Dana's romance with Peter were hopeful Venkman was Oscar's biological father but the theory has been proven illogical.

Some suggest Oscar is the offspring of Zuul and Vince Clortho when Dana and Luis Tully became possessed. However, assuming Oscar is roughly 8 months old and five years have passed between the films, the theory is highly implausible. The strongest theory that's been presented is Oscar's father is the violinist briefly shown in the first film who's referred to by Venkman as "the Stiff."

5 CROSSING THE STREAMS

While many fans of Ghostbusters were extremely disappointed with the 2016 reboot, they were delighted to see many of the original cast make cameo appearances. Operating outside the realm of the 1980s films, the reboot introduced a world where the original Ghostbusters never existed and the supernatural is seen as a myth.

The "Lethe Theory" posted on the Ghostbusters Fans webpage suggests the cameos have forgotten they were the original team despite their professions bearing an eery resemblance to "their past life." The most obvious example is Dan Aykroyd who despite being a taxi driver, recognizes the ghosts as "Class-5 full-roaming vapors" and references the film's famous theme song.

4 LAID TO REST

According to various news sites, Ghostbusters: Answer the Call-- the all-female 2016 reboot-- is regarded as the "most disliked trailer" on Youtube with currently 1.1 million "thumbs-down" reactions. With fans outraged over the need for a reboot and the gender-swapped cast, many were thoroughly disappointed with the treatment of their beloved franchise.

Considered a box-office disaster, the film received generally mixed-reviews with many agreeing the reboot failed to honor its original inspiration. Some felt the talents of the female cast were wasted on the lackluster film and diminished by backlash from anti-feminists. Despite the hate, the film managed to win a Kid's Choice Award and was nominated for a People's Choice Award.

3 A GOD AMONG MEN

In an interview with Esquire, Chris Hemsworth revealed his time as Kevin helped him with his performance in Thor: Ragnarok. Usually heavily-reliant on memorizing his lines and cues, Hemsworth was introduced to improvisation while on the set of Ghostbusters: Answer the Call. Originally, Kevin was meant to be a more apathetic character who became the team's secretary.

Feeling it was necessary to have the character be someone worth saving after becoming possessed, Melissa McCarthy suggested Hemsworth improvise and have Kevin be more of a lovable dim-wit. When it came to Ragnarok, Hemsworth's improv skills gave him the idea for the "Get Help" scene where he throws his brother Loki at a group of armed men.

2 TO HELL AND BACK

While it was recently announced that there would be a third installment in the Ghostbusters franchise, the journey to settling on a final script wasn't easy. Rumored to have had over five versions, each script introduced a new conflict the team would have to solve. The two widely accepted versions of what could've been the third film are Hellbent and New Blood.

In Hellbent, the team is transported to an underworld version of Manhattan where citizens have turned into evil versions of themselves. The big baddie in the film would've been the Devil himself known as "Luke Silfer." In New Blood, the gang realizes they're getting too old and seek a new team to carry on their ghost-hunting legacy.

1 WE CAME, WE SAW

Early this month, a teaser trailer was released announcing Ghostbusters 3 was in the works. Promised for Summer 2020, director Jason Reitman has remained tight-lipped regarding the main plot of the film.

Speculation has revealed the working title for the film is "Rust City" and will possibly feature a younger team made up of two males and two females roughly in their teens. Some rumors suggest one of these youngsters might be Oscar, Dana's son from Ghostbusters 2, who decides to carry on the family business. While actors Dan Aykroyd and Ernie Hudson say they'd be willing to make a return, official confirmation regarding cameo appearances has yet to be made.