One of the most popular sci-fi franchises of all time, the Ghostbusters films defined the '80s and became a cultural phenomenon. The combination of action, humor, and fantasy endured them as instant classics, launching an entire world of video games, comics, and animated series. In the '90s, fans waited for a third film to complete the trilogy, but although Ghostbuster star Dan Aykroyd was hard at work on a follow up feature, it never materialized.

Now at long last, the first trailer for Ghostbusters: Afterlife has arrived, igniting fans' curiosity and imaginations. Full of countless references to the lore surrounding the franchise, as well as promising new mysteries for the Ghostbusters to solve, it looks like it will be something both old and new fans can enjoy. Lets get down to the 10 most sensible theories about the new film, in theaters July 10th, 2020.

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THE GHOSTBUSTERS WON AND WEREN'T NEEDED ANYMORE

When we see a huge tarp over the Ecto-1 in the official trailer, it looks like the famous Ghostbusters ride has been out of commission for some time. The signature suits can be seen hanging in a closet, while a ghost box and and a proton pack are gathering dust in Egon's old farm house.

Some fans believe that after the last crisis in New York City in Ghostbusters IIthe Ghostbusters "won" and therefore weren't needed anymore as exterminators of the ethereal. Ray focused more on his Occult Bookstore, Winston started another career, Peter went back to Dana, and Egon was the only one still researching the paranormal. Paul Rudd's character explains there "hasn't been a ghost sighting in thirty years", implying that they went out of business shortly after the second film (and that the 2016 reboot doesn't count).

OSCAR IS GOING TO MAKE AN APPEARANCE

We've seen Egon Spengler's grand daughter in the new trailer, but we also see a variety of other children interested in Ghostbusters lore. Could one of them be related to Dana Barrett's baby with Peter Venkman, Oscar Barrett? Egon may not be the only Ghostbuster kin that has a role to play in the new adventure.

It's possible that Oscar Barrett may be the go between that the kids track down to reach his father and the other Ghostbusters. Originally fans thought Paul Rudd's character might be Oscar, but given the fact that he doesn't seem that familiar with a ghost trap, he probably isn't the child of Peter Venkman.

IVOR SHANDOR WILL RETURN

In a blink-and-you'll-miss-it moment in the new trailer, a sign for the Shandor Mining Company can be seen, established in 1922. Ivor Shandor, leader of the Cult of Gozer, would construct 550 Park West New York seven years later, using the building as a gateway to summon his deity to unleash Hell on Earth.

Shandor was the main antagonist in Ghostbusters: The Video Game, and has been said to have been behind many supernatural disturbances in the areas where his architecture is found. The strange materials that picked up signals from deep space were no doubt gained from the Shandor Mining Company.

A SUPERNATURAL RELIC WILL BE UNLEASHED

Should Ghostbusters Sequels Bring Back Harold Ramis With CG?

Given that Egon's grand daughter and friends spend time hanging around the Shandor Mining Company, it stands to reason that they might uncover some sort of ancient relic that releases a primordial presence similar to Gozer or Vigo the Carpathian. This could bring about a shockwave of energy that Paul Rudd's seismologist investigates.

While the seismic disturbances could be due to something awakening on its own, it's just as likely that the curious teens are the ones that unintentionally do the summoning. Among Egon's belongings and Ghostbusters paraphernalia, a few important artifacts might have been concealed to prevent the next apocalypse.

EGON COULD RETURN AS A GHOST

Ghostbusters Afterlife

Harold Ramis not only played the erudite Egon Spengler, he also wrote the first and second Ghostbusters films. With his passing, the Ghostbusters team is one man down. He knew the persnickety paranormal equipment better than anyone, and with him gone, the rest of the Ghostbusters may have struggled to carry on without him.

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It's possible that Egon's ghost might act as a spirit guide, and some fans have suggested that unused footage from the first two films could be used to make him an incorporeal entity. The Star Wars films have had some success with bringing deceased actors back to play minor characters, and the technology can only get more advanced.

THE BUSTED CONTAINMENT UNIT IS CAUSING EARTHQUAKES

The containment unit

Everyone remembers the Containment Unit in the basement of the Ghostbuster's HQ. Also referred to as the Protection Grid, it held all the mysterious vapors, ghosts, and spirits that the Ghostbusters trapped. When it was opened on orders by EPA inspector Walter Peck on his visit to the Firehouse, the psycho-kinetic energy was so powerful it ruptured the building.

Fans have theorized that the Containment Unit might have ruptured again, or that a unit that was installed on the Ecto-1 (like in the Activision Ghostbusters video games) somehow emptied its collection of ghosts wherever the vehicle is parked, releasing monsters and mayhem onto an unsuspecting public and accounting for all seismic activity.

THE KIDS BECOME THE NEXT GHOSTBUSTERS

The fact that Egon's grand daughter is the one who becomes particularly fascinated by her grandpa's paraphernalia indicates that she may well become part of the next generation of Ghostbusters. The theory is further amplified by the German trailer, which reveals more scenes of her and her friends firing proton packs while going joyriding in the Ecto-1.

The torch of the franchise needs to be passed to a younger generation, and the fact that it includes female Ghostbusters is a step in the right direction. Unlike the 2016 reboot, which had very little heartfelt connection to the other films, the fact that its Egon's grand daughter that leads the way should make the fanbase happy.

THE ORIGINAL CAST ONLY MAKE EXTENDED CAMEOS

Ghostbusters Original Cast

The cast for Ghostbusters: Afterlife is set to include Bill Murray, Dan Aykroyd, and Ernie Hudson as part of the original Ghostbusters team, with Sigourney Weaver returning as Dana Barrett and Annie Potts as Janine Melnitz. They weren't featured in the official trailer, but that doesn't mean they won't make a big impact somewhere in the film.

For some fans you can't have a Ghostbusters movie without the original Ghostbusters, but given their age (they're all in their 70's), they may not be involved in as much of the action as they used to be. Fans may have to settle for cameos, when the team is called in at the end to help solve a catastrophe too big for the teens that find Egon's equipment.

THE GHOSTBUSTERS ARE TRAPPED IN ANOTHER DIMENSION

Ghostbusters Devil Dog

In the animated series The Real Ghostbusters, which ran from 1986 until 1991, the Ghostbusters decided to rebuild the Containment Unit after the fiasco with Gozer. Egon Spengler made the modifications, one of which involved trapped ghosts being sent to a special "containment dimension" where they could fool around.

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This dimension changed from episode to episode, either resembling a dystopian underworld or a brightly colored area with card tables and diversions. Some fans have wondered if the Ghostbusters themselves didn't get trapped in a similar dimension at the end of the '80s, resulting in their complete absence for the past 30 years.

SOMEONE'S GETTING POSSESSED

Sigouney Weaver Dana Zuul Gatekeeper Ghostbusters

There are a few prominent adults featured in the trailer - Callie, presumed to be Egon's daughter, and Paul Rudd's seismologist. Other adult characters that weren't Ghostbusters in the films were Dana Barrett and Louis Tully. This leads fans to believe that either Callie or Rudd's character are getting possessed like Dana and Louis did by a Gozer-like entity.

We see brief flashes of a man with a shovel surrounded by keys (the Keymaster?!) confronting Rudd's character, and there look to be a few "demon dogs" prowling around in the trailer. If the Shandor Mining Company is the site of another Gozer event, someone is turning into Zuul.

NEXT: 5 Things We Need In Ghostbusters 2020 (& 5 Things We Don't)