I have been meaning to watch this movie for a while now and finally did. I had heard a lot of comparisons to District 9. I think both movies move at the same pace and that both movies are about aliens living on earth, but that is where the similarities end.
Monsters is one of those hidden monster movies that doesn't really reveal the full monster until the end. All you get are little snips or obscured views. These types of movies usually drive me nuts as I tend to get into the action with the mindset of how am I going to fight this thing. It is very hard to have that mindset when you don't know what the thing you are fighting actually looks like. This movie it wasn't so bad as we were seeing things through the eyes of the characters and they hadn't really ever gotten a good view of a living alien yet either. The payoff came with the long, steady, two alien scene near the end.
The plot is a trying to get back home story. The main characters are stuck in Mexico and need to get back the USA. The only way to get back seems to be by crossing through the infected zone. According to IMDB, the film was shot oppurtunisticly with very little scripting. The actors pretty much made it up, within the contstraints of the plot, as they went along.
The acting was okay. I am not familiar with either of the main actors. The guy, when he was talking to his son, did a pretty good job. While it wasn't noteworth great, nothing jumped out at me and said bad either.
Special effects in an Alien movie, you don't say. This movie cost less than a million dollars to make. considering how cool the aliens actually were, they must have spent almost every dollar on special effects. Yeah, less than a million dollars. compare this movie to War of the Worlds with Tom Cruise (132,000,000)and the bang you get for your buck is enormous. Not to mention that this was a way better movie than War of the Worlds.
Overall, this movie was a pretty entertaining watch. I have seen some comments about it being boring or slow, but I think I was aware that this wasn't going to be an action/adventure movie from the start. While the journey does take time, they do a good job of character development in those slow spots. I think most people will like this movie and should be okay for kids that won't get scared (you know who they are). Check this one out.