Gremlins. If you've seen the first of their movies, you probably think you know everything you need to about them.
1. Don't get them wet.
2. Don't feed them after midnight.
3. Don't shine any bright light on them.
4. Maybe shine a bright light on them when they're being evil?
5. ... they're usually evil.
Those are the three rules (plus the two I just made up) that most people would say are all you need to know about Gremlins.
But if you've seen director Joe Dante's Gremlins 2: The New Batch, you realize there's a lot more to it. Thanks to a Christopher-Lee-shaped geneticist, we know that, with a little bit of additional genetic information, Gremlins can adapt to become smarter, sexier, more ... vegetable-like? Bats, spiders, bolts of electricity ...
You name it, Gremlins can adapt to it.
But even that just scratches the surface. What if I told you that Gremlins 2: The New Batch was not, as you'd always assumed, a story of a New York City skyscraper under siege from a chaotic Gremlins force? What if, instead, Gremlins 2: The New Batch (always say the full title) is actually about a New York City metropolis that is the last stronghold existing in a post-apocalyptic world?
Does that sound crazy? Ridiculous? Oh, am I "reaching"? Take a seat, chum. Take all the seats. And then rearrange them however you like, because you're on the Gremlins equivalent of the Titanic and you didn't even know it.
Submitted for your approval is the following fan theory -- what if Gremlins 2: The New Batch takes place long after the Gremlins have already taken over the world? It's a lot less crazy than it sounds.