[3] Egon Spengler is a tall, lanky, laconic, bespectacled, handsome member of the team responsible for the main theoretical framework for their paranormal/quantum studies, having earned over a dozen advanced degrees including parapsychology and nuclear engineering from New York University and Massachusetts Institute of Technology, respectively.

He is socially awkward, as demonstrated by his stiff interactions with the Ghostbusters' secretary Janine Melnitz, and his reliance on Peter Venkman as a spokesperson for the group.

Of his hobbies, Egon states that he collects "spores, molds, and fungus", and claims that, as a child, the only toy he ever had was "part of a Slinky", which he straightened out.

Despite being a stereotypical timid professor-like figure, Egon is prone to violent reactions when pushed too far temperamentally, as demonstrated by his attempt to assault Walter Peck.

After Egon dies, the haunting in his farmhouse reveals that, like Ray, he was a skilled automotive mechanic, able to repair the Ecto-1's engine with his grandson Trevor as a poltergeist.

It is mentioned in the film's novelization that Egon's mother is alive, and he calls her after finding a payphone to inform his termination of his employment at Columbia University, while Peter and Ray discussing plans for the Ghostbusters business, explaining his absence on this scene.

When house-hunting for their headquarters, Egon was against Peter leasing the firehouse at North Moore Street due to its conditions and location (dilapidated wirings, neighborhood being plagued by criminal elements, etc.

), but Ray was attached to the building due to his fondness for its brass fireman's pole and the fact it was a place they could afford with their then-pitiful budgets.

Additionally a judicial restraining order was enacted which barred the Ghostbusters from performing services as paranormal investigators and eliminators, effectively putting them out of business.

Five years after the events of the first film Egon returned to teaching at Manhattan College, working at its Institute for Advanced Theoretical Research and was conducting experiments on human emotions, during which he invented the Giga Meter, a device similar to the PKE Meter designed to detect and measure psychomagnotheric energy in gigaelectron volts.

A negative test involved keeping a couple with marriage problems locked in a room for hours and gradually raising the temperature.

At trial they were found guilty by judge Stephen Wexler (whom Egon said was known as "The Hammer") of willful destruction of public property, fraud, violating their judicial restraining order, and malicious mischief.

While angrily insulting the trio, judge Stephen Wexler inadvertently released the ghosts of the Scoleri Brothers, two murderers he sentenced to death by the electric chair.

Egon had a dry sense of humor which he would use to bewilder Peter, and smirked at his friend's cluelessness as to what the word "epididymis" meant.

Eventually they developed "slime blowers", consisting of large metal tanks and handheld nozzles that fire positively charged substance.

Despite the Ghostbusters successfully closing the "Manhattan Crossrip of '84", at some point after the "Vigo Incident of '89", Egon had discovered prophecies written by the Cult of Gozer's prophets saying Gozer would return in 2021, but his insistence that the Ghostbusters prepare for this strained their relationship (a nod to the real-life estrangement between Ramis and Bill Murray after their collaboration in the film Groundhog Day), and preparing for the events of the prophecies is the reason for his distance with his daughter, who he intended to protect.

He is revealed to be a collector of strange artifacts, like a death whistle from the Aztec culture similar to the ones first discovered by archaeologist Francisco Rivas Castro in 1999, some witch bottles hanged on his dead trees, and Sentinel figurines from Shandor's Gozerian Temple, and still eating junk food.

Egon's death results in Callie and her two children, Trevor and Phoebe, moving from Chicago to Summerville to take possession of his house and belongings.

Though unseen by his family as a poltergeist (Class 2 or 3, noncorporeal and telekinetic), Egon's presence guides Phoebe into continuing with his plan to defeat Gozer, and she eventually stages an ambush after forming her own Ghostbusters team.

Outside of archived audio clips, Egon has no speaking lines throughout the film and his face was obscured in present-day shots until his return as a ghost.

The likeness of Harold Ramis was recreated digitally for key shots in conjunction with body doubles (Bob Gunton and Ivan Reitman).

Egon sometimes appears to be unaware of Janine's romantic interest in him, but at times he displays having similar feelings for her, such as when he gave her a geranium as a gift when she expressed an interest in plants (which backfired horribly when it was revealed that the geranium was possessed by a ghost and nearly destroyed her apartment, along with much of Brooklyn; though Egon managed to thwart the ghost, Janine angrily told Egon he would have to pay for the damages to her home) and when he rushed to her rescue in "Janine, You've Changed"; he also embraces her in "Ghost Busted" after she was kidnapped and held for ransom by a gangster, and became jealous when she was briefly involved with a slimy businessman named Paul Smart.

Before the "Return to Sedgewick Hotel" mission, Stantz comments that Egon was once a coroner, to which he replied that he maintains interest in the subject as a hobby.

According to a message left on the Ghostbusters' answering machine, Peck made calls that canceled Egon's orders for parts that he needed with pleasure.