May contain spoilers.
First off the movie was great. The only thing negative I can say about it is, within the first 30-45 minutes I had a hard time believing the movie was attempting to be serious. Most notably the aliens acting so much like humans, or better yet, the aliens being treated so much like humans. This should be no more difficult to take in than any other alien depiction (since we know nothing about them) but when they were going from door to door asking them to sign eviction notices... well, it was more humorous than anything. But as the movie progressed it became much easier to take in. Everything else was solid. Extremely interesting. And they did a great job instilling a sense of sympathy towards the aliens from the viewer. While I can't say the movie started out great, it did get better with each passing minute and the ending was perfect, paving the way for a possible sequel. Overall the movie was very original in the way it was written and the acting was on point, especially from Sharlto. Definitely worth checking out. Great movie.
Surprisingly the movie is currently #28 on the iMDB top 250 with an 8.8