9 Movies You Didn't Realise Are Set In The Same Universe

This one makes probably the most sense out of anything on this list. Both franchises are centered around the paranormal, both have been presented as cartoons and live-action films, and both are family-friendly. Really, it only makes sense that one day the Ghostbusters would be called on to extinguish everyone's favorite, misunderstood apparition.

That happened in the 1995 when Dan Aykroyd, dressed in full ghost-busting regalia, appears in the Casper movie. He was called in to exterminate Casper's extremely rowdy uncles from a dilapidated mansion, but high-tails it after one of the dastardly apparitions breaks his proton pack.

And just in case any skeptics out there don't think that constitutes an "official" crossover, Aykroyd's jumpsuit has the name "Stantz" stitched on the front lapel, and he even lampoons his own famous catchphrase, saying to those who hired him: "Who ya gonna call? Someone else."

There's also a cameo by Father Guido Sarducci -- a chain-smoking Italian priest that was a popular character on Saturday Night Live in the early years -- who is called into the same mansion to perform an exorcism. By extension, this means the Ghostbusters exist in the same universe as the Bundy family from Married...With Children, since Father Sarducci made a guest appearance on that show, as well.