7. Weir Is A Hellraiser Cenobite - Event Horizon
From the focus on extreme body horror to its themes of blurring the line between pain and pleasure, Paul W.S. Anderson's Event Horizon more than earned the "it's Hellraiser in space" comments when it released, as the movie plays out incredibly similar to its obvious influence, only with a harder sci-fi edge.
However some theories state that the connections go even deeper than homages (or blatant rip-offs, depending on your opinion of the movie), and that the two films actually take place in the same universe. Sure, Event Horizon brings about an orgy of bodily destruction thanks to a wormhole to Hell rather than a puzzle box like in Hellraiser, but there's plenty to suggest these two alternate dimensions are one and the same.
First up is the relationship between the Cenobites of Hellraiser and the monsters of this movie, both of which take perverse pleasure in torturing their victims, and getting them to lose themselves in sadomasochistic activities. Of course Pinhead and co. don't pop up, but it's argued that's because main character Weir is actually transforming into the alpha Cenobite of this realm after he returns from his trip to the underworld, mangling his own body and becoming "enlightened" about what he saw down there.
Throw in the obvious visual similarities, as well as haunting lines like "I have such wonderful things to show you" which are almost word for word lines from Hellraiser, and Event Horizon could genuinely be a sequel in disguise.