I recently saw this rather disturbing film, and it is also very interesting, scary, and shocking. It is almost twisted and dark if you plan on going into the mind of a serial killer. And, it is most certainly like going into the world of surreal and twisted sense of reality to which you have to break through to find the answers. Personally, I think this movie is an interesting look at one's twisted mind to which there are two "selves:" a wounded child (inner self) and an evil predator (false self).
While I think the acting on Lopez's and Vaughn's parts were good considering, the story and the depiction of how the mind works when a inner self was suppressed and a false self took over was very interesting and it has some harsh truth to it: it can happen in real life where one do not have control over oneself.
"The Cell" is a great title for this movie as it shows a prison for that inner self (a wounded child) while the false self controls everything.
It is really good film to watch, in my personal opinion.