Three former parapsychology professors set up shop as a unique ghost removal service.
Peter Venkman, Ray Stantz and Egon Spengler work at Columbia University. where they delve into the paranormal and fiddle with many unethical experiments on their students. As they are kicked out of the University, they really understand the paranormal and go into business for themselves. Under the new snazzy business name of 'Ghostbusters', and living in the old firehouse building they work out of, they are called to rid New York City of paranormal phenomenon at everyone's whim. - for a price. They make national press as the media reports the Ghostbusters are the cause of it all. Thrown in jail by the EPA, the mayor takes a chance and calls on them to help save the city. Unbeknownst to all, a long dead Gozer worshiper (Evo Shandor) erected a downtown apartment building which is the cause of all the paranormal activity. They find out the building could resurrect the ancient Hittite god, Gozer, and bring an end to all of humanity. Who are you gonna call to stop this terrible world-ending menace?
After delving into the supernatural one time too many, the scientists and ambitious paranormal researchers, Dr Peter Venkman, Dr Raymond Stantz, and Dr Egon Spengler, find themselves out of work. Intent on proving everyone wrong, the team comes up with "Ghostbusters", a paranormal search-and-destroy service, targeting the Big Apple's rogue spirits, until they come face-to-face with the ancient shape-shifting demon, Gozer the Destructor. Now, the possessed former client, Dana Barrett, and her love-smitten neighbour, Louis Tully, are up to something, eager to usher in a new era of evil. For the first time in their career, the Ghostbusters are on to something big; however, do they have what it takes to thwart the interdimensional entity's malevolent plans?
Three odd-ball scientists get kicked out of their cushy positions at a university in New York City where they studied the occult. They decide to set up shop in an old firehouse and become Ghostbusters, trapping pesky ghosts, spirits, haunts, and poltergeists for money. They wise-crack their way through the city, and stumble upon a gateway to another dimension, one which will release untold evil upon the city. The Ghostbusters are called on to save the Big Apple.
After being kicked out of their university, parapsychology professors Spengler, Stantz and Venkman decide to go into business for themselves by trapping and removing ghosts from haunted houses. After some initial skepticism, business is soon booming as The Ghost Busters rid New York of its undead. When a downtown skyscraper becomes the focal point of spirit activity linked to the ancient god Gozer, however, the problem may be more than the team can handle.
- The film opens within the New York Public Library, where a librarian (Alice Drummond) is first gathering books, before heading downstairs to a remote and empty section. She places a book back on the shelf, not noticing that the books behind her are levitating across the aisle. Later, she passes the card catalogue shelves as they open behind her and suddenly begin to hurl their contents into the air. Frightened and screaming, she runs through the room before being stopped by an unseen ghost, which scares her terribly. This leads into the title card.
After the opening title shot, the film continues in the Paranormal Studies Dept. of Columbia University, where Dr. Peter Venkman (Bill Murray) is conducting a test on ESP with a nerdy male student (Steven Tash) and an attractive female student (Jennifer Runyon). Venkman continually flirts and lies about her abilities, while enjoying administering electric shocks to the male student. Having finally had enough, the male student departs, and Venkman continues to flirt with the young woman. Dr. Ray Stantz (Dan Aykroyd) enters, and frantically begins to tell Venkman about the sighting at the library, insisting they leave at once to check it out. Venkman makes a date with the student, and follows Stantz out.
Upon arriving at the library, Venkman and Stantz meet up with Dr. Egon Spengler (Harold Ramis), and Venkman proceeds to ask a series of personal (and cynical) questions about her medical and social history, before the three head down to the area the ghost supposedly inhabits. While down there, the three men collect ectoplasmic residue, discover a tall "symmetrical stacking" of books from floor to ceiling, and narrowly escape a falling bookcase.
Turning the same corner as the librarian, they see the ghost: a transparent form of an elderly lady (Ruth Oliver), reading a book. Having no idea what to do, Venkman begins to talk to the ghost as if it were a lady in a bar. She shushes him, before Stantz proclaims he knows what to do. They stealthily approach the ghost, before Ray yells, "Get her!" and the ghost mutates to a ghoulish, skeletal apparition, scaring the hell out of the trio, who run screaming from the library. They ignore the library administrator (John Rothman) in their frantic way out.
After they've calmed down a bit, they walk back to the university. Venkman mocks Ray's idiotic plan, and Egon announces that based on his readings, they now have a "good change of actually catching a ghost and holding it indefinitely." However, once they get back to the school, they meet the dean (Jordan Charney) who tells them that their grant has been terminated due to their shoddy and highly suspect findings, research, and methods.
Peter and Ray sit drinking on campus, and Ray mopes about their bleak prospects, before Peter suggests this turn of events happened so that they could go into business for themselves, as the world's first firm for paranormal investigations and eliminations.
Peter convinces Ray to take out a mortgage on his childhood home, and use it for startup capital. The trio checks out an empty firehouse to use as a headquarters, and while Egon enumerates the many problems with the building itself, Ray is beside himself with excitement at the prospect of living and working there, specially with the fire-fighter pall in the middle of the hall.
At 55 Central Park West, classical musician Dana Barrett (Sigourney Weaver) arrives home with groceries. Her neighbor, übernerd and accountant Louis Tully (Rick Moranis), stops her in the hall, telling her that her television had been left on. Louis badgers her about an upcoming party he's hosting, and Dana finally brushes him away and enters her apartment. As she is putting away her groceries, she notices that her eggs are now leaping out of their shells and cooking themselves on her countertop. She then hears a growl coming from her refrigerator, opens it, and sees an otherworldly temple, and a doglike creature that growls the word "Zuul" (voiced by Ivan Reitman), before Dana frantically slams the door shut.
Back at the newly christened Ghostbusters headquarters, Ray pulls up, shocking Peter with the new business car, an old beat-up ambulance that needs a lot of work. Peter goes back inside, makes small talk with their new secretary, Janine (Annie Potts), and waits around for business.
Dana arrives seeking an explanation for the events in her kitchen. Peter flirts vigorously with her, while Egon and Ray examine her briefly, and speculate as to what may be the cause of her encounter. After deciding on a plan of action, Peter insists on going with Dana back to her apartment, where he haphazardly looks around, but mostly flirts with her. He looks in the kitchen, and sees the eggs on the counter, but nothing else out of the ordinary. Dana is annoyed, but Peter continues to beg her for a date, pledging to solve her problems in an effort to impress her.
Later, the Ghostbusters sit around enjoying dinner celebrating getting their first customer, but Ray has to let them know that the meal has just used the last of the business' petty cash. Fortunately, even as the business' failure is staring them in the face, Janine finally gets an urgent call about a ghost that needs removal immediately. Peter, Ray, and Egon quickly dress, and race out of their headquarters, to the Sedgwick Hotel, where the manager (Michael Ensign) informs them of a ghost on the 12th floor. They've always had problems, he tells them, but lately it's gotten out of hand. The Ghostbusters assure him they'll take care of it, and head up to the 12th floor. Egon and Ray worry about their equipment, which Peter describes as an unlicensed nuclear accelerator, and decide that they'll ignore the danger for now. They make chitchat conversation with a guest (Murray Rubin) outside the elevator, and they tell him they are going to kill a cockroach, to which the guest answers, "That's gotta be some cockroach." He takes the next elevator.
Almost immediately after the Ghostbusters exit the elevator, a maid startles them, and they nearly kill her with their proton packs. The three split up, and Ray eventually sees the ghost: a rotund, green blob, eating everything on a room service cart. Ray tries to hit it with his proton pack but misses, and it flies away, frightened. Ray calls Peter on his walkie-talkie, and Peter, who is now face-to-face with the ghost, is suddenly attacked by it. Ray runs to Peter, and finds him on his back, covered in green slime, but otherwise OK. Egon calls them and informs the other two that the ghost went into the hotel's ballroom.
They calm the hotel manager, and then set to work on containing the little green ghost. While shooting their weapons all over the room, Egon suddenly warns the others not to cross their streams, because to do so would result in the destruction of "all life as you know it." After destroying much of the ballroom with their seriously unstable proton packs, the Ghostbusters finally trap the ghost, and burst triumphantly from the ballroom, before the anxious manager and a host of guests burst in. The Ghostbusters haggle with the manager over the $5000 bill for a moment, and then head back home, victorious.
This successful hunt proves to be but the first of a sudden rash of hauntings mean brisk business for the Ghostbusters. There is a montage of a series of missions, news spots, newspaper clippings, and stories about the Ghostbusters' new fame and success. There are even interviewed by Larry King and Joe Franklin (themselves).
Peter briefly meets with Dana after her orchestra practice, and flirts a bit with her before telling her about Zuul, whom he has discovered is associated with an ancient Sumerian god of destruction, Gozer. He tells her that he'll go over it in more detail over dinner, and finally, she agrees to a date.
The Ghostbusters soon hire a fourth man, Winston Zeddemore (Ernie Hudson), a black, blue-collar type guy, who is just looking for a job. Hired immediately by Ray and Peter, Winston is handed a couple of traps and led off by Ray to learn about getting rid of the ghosts, while Peter is informed that there is a man from the EPA waiting for him.
Walter Peck (William Atherton), the pompous EPA delegate, condescendingly talks to Peter, refusing to acknowledge that Peter is, in fact, a PhD, and therefore, Dr. Venkman, and briefly questions him about the possible environmental impact of their business, and specifically, their custom-built storage facility. He demands to see it, but Peter just patronizes him for a bit before throwing him out.
Ray shows Winston how they unload the ghosts they've trapped into the storage facility, while Egon admits he is worried about the facility's looming capacity problem and the larger problem it indicates. To illustrate, Egon tells them that his latest research indicates that the city is experiencing a colossal increase in paranormal activity, comparing it to a 600-pound Twinkie. Peter joins them, mentioning the EPA, and memorably asks, "What about the Twinkie?"
A brief shot on the top of Dana's building shows that dog-like gargoyle statues atop the roof are breaking apart and real animals are underneath the stone.
Back inside, Dana arrives home, and is once again accosted by Louis who is raving about his party. He is disappointed when Dana tells him she has a date. She gets rid of him again, and goes into her apartment, undressing and talking on the phone. She sits in an armchair for a moment before noticing the same growling sounds from the kitchen. Before she can react, three arms burst from the chair and hold Dana down as she is dragged through her kitchen door to one of the Terror Dogs. Another shot on the roof shows that the gargoyles on the roof have completely broken apart, and whatever was in them is loose.
Louis' party continues as he rambles on about the price efficiency of his hosting a party. Two guests show up, hand Louis their coats, and he throws them -unnoticing- on the terror dog sitting at his desk. It roars, and bursts through the door, apparently only after Louis. He runs out of the apartment, through Central Park, before being cornered and attacked outside Tavern on the Green.
Meanwhile, Peter arrives at Dana's apartment, stepping over the carnage of Louis' party, and knocks on the door. Dana opens it, dressed in a slinky red dress, and asks, "Are you the Keymaster?" Peter says no, so she angrily slams the door in his face. He knocks again, and enters after answering her question "yes". Dana says that she is Zuul, and they must prepare for the coming of Gozer, The Destructor. Peter talks to her and resists the possessed Dana's aggressive advances, before requesting to speak with the real Dana. At first, Dana coyly replies "There is no Dana, there is only Zuul," trying to kiss him but Peter, still trying to get through to the real Dana Barrett, restrains her. The possessed Dana now becomes visibly annoyed at his persistence, as Peter once again inquires about the real Dana; she replies in an unearthly demonic voice "There is no Dana, only Zuul!" Peter sarcastically dismisses her and gives her to the count of three to talk to the real Dana. With each count, Dana presents further signs of her possession: at first demonically rolling her eyes, then panting like an animal, and finally roaring like a demonic beast and magically floating above her bed. She turns over in midair, to face down at Peter whom asks her to please come down. Dana roars fiercely at him, finally frightening him.
Louis, looking disheveled and generally abused, runs out from Central Park rambling, and asks a hansom cab horse if he is the "Gatekeeper". The driver (Danny Stone) chases him off, so he runs away, screaming about a sign of Gozer's arrival.
The NYPD arrives at the Ghostbusters headquarters, to drop off Louis, who's been captured and rejected by both the city jail and Bellevue's psych ward. Egon looks at him briefly, and takes him inside. Louis reveals his name is Vinz Clortho, Keymaster of Gozer. He goes on about the history of Gozer, how the god assumes various forms and would mean the destruction of the civilization he targets. During the exam, Peter calls, and tells Egon about the developments with Dana, who is now lies heavily sedated on the bed next to him. Egon tells Peter in return about Louis' psychic transformation, and insists Peter come back to headquarters.
Winston and Ray are driving back to the office, Winston driving while Ray examines the "very odd" blueprints of Dana's apartment building. Winston asks Ray about his belief in God, and speculates that the reason they've been so busy lately is because the dead have been rising from the grave, as it was foretold in the Book of Revelations, as a precursor to judgment day, and the end of the world. Ray ponders this.
Back at headquarters, Walter Peck has returned with a court order, a cop, and a Con Edison worker (Larry Dilg), intent on shutting down the storage facility. Egon tries to talk them out of it, and Peter arrives just in time to antagonize Peck some more, before the cop intervenes and the Con Ed guy, although highly reticent handling equipment he has never seen before, shuts off the power grid. A warning buzzer sounds, and everyone clears the building, as the storage facility rumbles and begins to destroy the basement.
A supernatural light show occurs, as all kinds of paranormal energy bursts through the building and shoots out of the roof. Across town, Dana, immediately wakes up from her sedation, and walks toward her living room window. Louis is excited, claiming this is the sign he was waiting for. Ray and Winston arrive to witness the disaster's immediate aftermath even as Peck demands they all be arrested for causing it. Enraged at this self-righteous blowhard outright lying about them while ignoring his own responsibility in this disaster, Egon attacks Peck, getting everyone arrested.
Ghosts run rampant through the city, but most of the energy seems to run directly to Dana's building. Dana growls at the energy, ripping out the wall of her apartment in a small explosion.
Sitting in jail, Ray shows Egon and Peter the blueprints of Dana's apartment building, pointing out highly unorthodox methods and materials, especially near the roof. Egon tells them that the building, he's discovered, was designed by an insane architect/surgeon named Ivo Shandor. In the 20's, Shandor was evidently so disgusted by the First World War, that he decided he would try to bring about the end of the world with a secret society of Gozer worshippers. They performed rituals atop Dana's building, and the roof itself was meant to be the gateway to allow Gozer into our world. A guard arrives (Reginald VelJohnson), and tells the Ghostbusters that the mayor wants to meet them, to deal with the rash of ghosts and other unbelievable phenomenon happening throughout the city.
Louis arrives at Dana's demolished apartment, introducing himself as the Keymaster. A smiling Dana responds she is the Gatekeeper and they share a passionate kiss before slowly making their way up to the roof via a mythical staircase behind the wall where Dana's fridge used to be as lightning flashes ominously.
The four men and Peck are brought before the Mayor (David Margulies) both arguing their sides. Peck claims the Ghostbusters are con artists and use nerve gases to force people to hallucinate and have visions of ghosts. Winston steps up and defends the things he's seen as real while numerous city officials like the Fire Chief present evidence of bizarre phenomena of which the Ghostbusters have the only possible explanation. Ray reveals that the city is headed for a disaster of "biblical proportions", and Venkman finally appeals to the possibility that the mayor could be responsible for saving the lives of millions of registered voters. Convinced, the Mayor throws Peck out of his office and offers whatever support he can to the Ghostbusters.
People have gathered all around the apartment building, which has clearly become the center of the entire mess. They cheer as the Ghostbusters arrive with a police escort and following National Guard troops, and Peter mugs for the crowd. The four men put on their proton packs and are prepared to enter, but a sudden earthquake seems to swallow them beneath the street. Eventually, they emerge unharmed to the continued cheers from the crowd. They band together and head inside.
Once inside, they must climb the stairs to Dana's 22nd floor apartment. Dana and Louis lie on a large stone table as lightning flashes in the dark sky above them. Dana seductively wakes up, followed by Louis. They stare in awe at the large Temple in front of them then walk toward the opposite stone pedestals where the Terror Dog statues once stood. The Ghostbusters arrive to find Dana's apartment burned out and more or less destroyed. They see the staircase in the kitchen and go up.
Dana and Louis stand on their pedestals and raise their arms to the sky. They are suddenly struck by bolts of lightning which they redirect toward the temple door, causing it to grind open and signaling the arrival of Gozer the Gozerian. With the temple doors finally open, Dana and Louis now absorb their full power as the Ghostbusters arrive just in time to see the lightning converge on the demonic couple in a huge blast, transforming them back into the monstrous Terror Dogs, who now turn and roar menacingly at the Ghostbusters before leaping towards the side of the Temple doors.
Gozer appears in the form of an exotic female with a tall, dark flattop and blood red eyes (Slavitza Jovan). Egon points out that she's not really a woman, but rather, takes the shape of whatever it wants. Peter goads Ray into talking to her. Ray very formally requests that Gozer returns to her place of origin, but she responds by asking if he is a god. He says no, and Gozer responds by shooting lightning from her fingers and nearly hurling the Ghostbusters off the roof.
They regroup and decide to attack Gozer, but she nimbly jumps clear of their streams and lands behind them. Another attack proves fruitless as she disappears rather than being caught in the streams. Believing they are victorious, the Ghostbusters begin to celebrate, but it is short-lived as Gozer's booming voice is heard above the city demanding that they "choose the form of the Destructor".
Peter tells everyone to clear their minds, and think of nothing, so no form will be taken, but it is clearly too late. Ray admits he did his best, but something just popped in his mind, something he thought could never harm anyone. "It's the Stay Puft Marshmallow Man."
A 10-story, white, puffy marshmallow man begins to walk the streets of the city, crushing everything underfoot. When he is close enough, the Ghostbusters open fire, setting Mr. Stay Puft ablaze, as he begins to climb the building, King Kong style.
Running for cover, the Ghostbusters appear out of ideas, until Egon suggests that they cross the streams, in an effort to close the door, and destroy Gozer's portal. Realizing this will probably mean their doom, the Ghostbusters go ahead with the plan, and set off to finish the god.
Crossing the streams does indeed result in a catastrophic explosion, destroying the temple and incinerating the Stay Puft Marshmallow Man, raining molten marshmallow all over the street, including an onlooking Walter Peck.
Back on the roof, the Ghostbusters have survived, and slowly emerge from the rubble, covered in marshmallow. Peter finds the roasted carcasses of the Terror Dogs, and believes Dana dead. Behind him, though, her fingers crack through the hardened ruins of the animal, and the Ghostbusters quickly break apart the rest, freeing her and Louis. They leave the roof, and Winston exclaims, "I love this town!"
As the closing credits roll, the Ghostbusters return to the street to the roaring cheers of the crowd. Peter and Dana kiss in front of everyone, Louis is helped into an ambulance, and as they drive off, the green ghost from the hotel roars toward the camera as it fades to black.