Epic clash between survival, thriller, and action. This could very well be one of the best movies Will Smith has ever done!
In this movie, there was an equilibreum between horror and action, and that is what makes a great thriller. This movie was not the let-down like people were saying that it would be.
As the movie goes on, you get more and more intrieged and consumed by the story. You want to find out more, you want to know how. It keeps you litteraly at the edge of your seat waiting for something to happen, and when something does, you involuntarily jump back several inches.
Overall, I would highly recommend this movie, and I will go and see it again. You will not be disappointed.