To me, this is basically what a good science fiction film should be; Take a concept that cant exist in our world, then explore all the logical consequences of it.
Idealy the concept should be something not seen before, and not just a trivial extrapolation of stuff we have right now.
This film does exactly that.
The film is set in and between two worlds. Two planets side-by-side, each with completely independent gravity planes. Everything from a world is only attracted too its native world. So, effectively, mater and thus people from the different worlds get pulled in different directions.
This is, of course, nothing like how gravity works in our universe - but thats not the point. This is a different universe, and once you accept those rules it explores it wonderfully.
, Reviewed By Darkflame
Upside Down created by nobody