I seen this movie almost 7 years ago.. but I’m sure it was older. The plot of the movie is as such. There was an alien invasion.. and the remaining humans were kept in a camp of some sort. The cam had very high walls.. there was some kind of well in the middle of the camp that the guy in charge would throw people in to as a punishment or something.. there was a creature in the well that would eat them. Any way.. the protagonist was a woman with a daughter.. u find out that the people in charge are robots.. and they make the woman fix them under threat of them hurting her daughter.. when they finally figure out how to defeat the robots.. they find out that the aliens have been gone  for a long ass time.. and the robots were left there to keep them in this camp until they all died… when they finally opened the door to the camp.. they found that nature had grown back and it was all pretty and untouched by humans for a long ass time…. oh.. and I think they were told that the air is toxic.. I have a crisp high 5 for the person who can tell what movie this is so that I can watch it.