Are they humans?

So just watched the first movie last night and haven't read the books. I feel like I missed something. They talk about being divergent like it's a rare quality. Obviously all humans in our reality have multi-faceted personalities. It's not at all unusual to be want to be smart, and brave, and compassionate, and honest and whatever the other one was. So are these people supposed to be some sort of alien-hybrid or cyborg or were they all drugged by the government? What exactly made them all so dull? I'm hoping the answer is in the sequels because I find the entire premise to be pretty ridiculous if they're saying people can just be put in some random personality box. I figured it would turn out that all the people were divergent but then they were the only ones not affected by the mind control drugs.

Please feel free to post spoilers as I probably won't watch anymore if we're just supposed to accept that humans are that one-dimensional.