The game's story opens in 1991 with another of the Ghostbusters' television commercials.  It's good to see that fame hasn't changed the guys, as their television performances are still just as wooden and awkward in 1991 as they were back in 1984.

When we first see Slimer, he's in a cage in the Ghostbusters firehouse headquarters where he's testing his psychic abilities with Peter Venkman's ESP cards.

Most of the best references are found in the firehouse.  Consider the wall behind Janine Melnitz's desk, for instance.  It's loaded with newspaper clippings about the Ghostbusters, some of which are from the music montage midway through the first film.  There are even some new clippings mixed in which show images from Ghostbusters II as well.

Speaking of Ghostbusters II, I've already shown you Vigo the Carpathian's painting in a previous PTB article. He can predict the future, by the way. Listen to him long enough and he'll talk about the O.J. Simpson murder trial and George W. Bush's two-term presidency.

Did you know that the Ghostbusters have an Employee of the Month program?  I have a feeling that it was Venkman's idea, considering that he's won the honor every time.  Well, almost every time.  Winston Zeddemore must have commented on Venkman's streak in July, granting him the award that month.

Despite not appearing in the game, accountant Louis Tully is still on the company payroll.  Here's his wreck of a desk near the front of the firehouse.  Why is he not at work today?  According to the note he left taped to his computer monitor, he wasn't feeling well and went home early that day.  Note the spare Ghostbuster uniform hanging on the wall just in case he has to suit up in an emergency.

Granted that one generic camcorder looks like any other, but does anyone else think that this camera in a box on the firehouse's second floor resembles the one that Ray Stantz takes to the library in the first film?

Have you ever played the old Ghostbusters video game for the Nintendo Entertainment System?  Someone in the firehouse has.  That's the poorly spelled endgame screen on that computer monitor there.

Nice logo-branded coffee mug there in the firehouse's kitchen area.

The team doesn't really do birthday party appearances anymore, but they still have some of the decorations.  Here's a HAPPY BIRTHDAY banner partially hanging upstairs.

Remember when the Ghostbusters updated their logo in 1989 when they went back into the paranormal investigation and elimination business?  The Ghostbusters II logo advertised their presence in the firehouse for a while, but by 1991 the team had replaced it with their traditional logo.  They kept the sign though.  You can barely see it in storage in an inaccessible area near the staircase that leads to the containment grid.

There are several cursed artifacts to collect during the course of the game that are not severed stone heads or haunted disco pants, but are actually Ghostbusters toys and merchandise.  Check out the remote control Ecto-1, Stay Puft Marshmallow Man doll, and a DVD of the first film (which, as the set-in-1991 game notes, is from the future).

While the iconic proton pack has been upgraded with new technology, some of the older models and prototypes are still stacked around the firehouse.  Check out Egon Spengler's workbench near the basement and you'll find PKE meters other technology from not only the films, but also from animated series The Real Ghostbusters and Extreme Ghostbusters.  How's that for reaching out to each incarnation of the franchise?

Moving on from the firehouse, the Ghostbusters can't go back to the New York Public Library without encountering some symmetrical book stacking. No human being would stack books this way.

There are many fantastic plot elements to experience during the course of the game that tie up loose ends from the two films and provide answers to questions you didn't even realize you had, so while I'm not about to spoil everything here, there's one last bit of awesomeness that I can't leave alone and it's a very important moment from the end of the game, so here's your spoiler warning.  Stop reading now if you'd prefer not to know the incredible revelation.  For some buffer space I'll just share some of my favorite moments with the Stay Puft Marshmallow Man.

Speaking of Stay Puft, we spend the entire game hearing about Gozer the Gozerian and his followers in the Shandor cult who are attempting to summon him back to our dimension, but aside from the deity appearing again in Destructor form as Tubby Softsqueeze, we never actually see Gozer as we saw him at the end of the first film when he appeared as Serbian model Slavitza Jovan.  As the final boss encounter starts to unfold, we finally get to see Gozer as we remember him... er, her.  And she's not doing so well these days.  After failing to destroy the world twice, Gozer's followers declare the Sumerian god to be unworthy of their devotion, and I guess it's true because the leader of the cult has Gozer's dead decapitated skull!  And it's clearly Gozer.  Check out the hair.  It's unmistakable.

For as much as Ghostbusters: The Video Game gets right (and despite its technical glitch sins (more on that later)), the best thing that it has going for it — and this is extremely rare for a game based on a licensed property — is that it respects the franchise and, moreover, its fans.  One could blast right through this game without noticing these fun little hidden additions, but fans of the films, the characters, and the story itself can easily lose an hour or more checking out all of the in-jokes and references.  This game is definitely for the fans, and believe me, it's appreciated.

(Thanks to Toad64 for the screenshot of the haunted Ecto-1 entry of Tobin's Spirit Guide)