Far from a perfect movie, but it does many things well. In particular, 85% of the effects are really good and almost all of the camera work. The story as a whole is good. The problem is in the details. A bunch of the specific plot points necessary to get from one place to another don't make sense. The dialog is overall really horrible which undermines the serviceable cast (except Dakota Fanning who is talented). I think the acting would have been fine if the dialog wasn't so bad.