Patema Inverted is a film about a split world where gravity points in different directions. This affects people, objects, and even natural stone. Wherever an object was created decides which direction the object falls. Of course, without some kind of protection, objects and people can fall into the sky.
That's the concept. As a concept, it's incredibly interesting. The gripping moments, awesome actions scenes, and interesting animation sequences have limitless potential. This movie fills that potential and does a fantastic job of executing the concept in a way that keeps things interesting.
Unfortunately, that's one of the only things the movie did exceedingly well. The pacing of the movie was strange. It started rather slowly until some revelations by the characters drew us into the action. The film takes a large amount of time to introduce us to Patema, one of our protagonists. While this is a good thing, Patema isn't an incredibly interesting character. She's the Chief's daughter, sure, but that only comes into play for a few lines of dialogue. She has some really emotional scenes that just don't feel as emotional as they should because the character depth isn't quite up to snuff.
In addition, Age, the other protagonist, doesn't get the same treatment Patema does, at least not right away. Until later in the movie, the only things we really know about Age is that he isn't happy with the authoritarian nature of his school/government.
The antagonist of the movie and the rest of the supporting cast are all extremely one-sided: dumb, in love, mindless goons, etc.
While the pacing is inconsistent and the movie starts off slow, once it hits its pace, it really takes off. The two protagonists really help develop each other, although the short amount of time it takes for each one to be willing to sacrifice their lives for the other is much too short.
Altogether, the plot is a means to an end. It is designed to force the characters together so their one-sided-ness isn't nearly as glaring as well as to give us a reason to see the world. The twist at the end wasn't terribly surprising, but it was executed well.
All in all, the movie was good, not great. The concept was fantastic, but the rest of the movie just held the concept back. It's certainly worth a watch (probably two), but it isn't something I'll make a point to watch at least once a year.