Monster: 8 out of 10.
If I didn't know that was Charlize Theron playing the role of Aileen Carol Wuornos I wouldn't have guessed it in a million years. This is a seriously awesome performance by Theron and it makes the movie. Her Oscar was well deserved, I'm surprised they didn't give her two.
This isn't a feel good movie, in fact, it's downright depressing. As difficult to watch as it is, it's also a very good flick and those are few and far between.