First, Sandra Bullock is appealing in what she is in. Just a great actress that is easy to relate to. As usual, she does a great job and runs the spectrum from vulnerable to strong as the movie goes on. Really, all the actors did great, there just wasn't a lot of character development for most of them and perhaps it wasn't needed, as the story is really centered around Sandra's character. It is a little strange, to say the least, but it doesn't really take away from the movie. Personally, I would have liked a little more transparency as to what exactly was causing the apocalyptic type of behavior, but that is also part of the movie, that it is kind of left up to our imagination. Definitely worth a watch, but not the type of movie I would see multiple times.