do you think it's worthy watching it? [spoiler]
Attention: it might contain a spoiler.
[spoiler]I just watched it and I doubt it's been worthy. There's some psychological stuff going on in the cell. The story itself offers the viewer no conclusion whatsoever, the prisoners start to use the book and find themselves in prison again.. and from there there is no escape. The movie ends. This, more than an horror film it should be classified as a pervert psychological film where going against nature is the topic of the day. How sick must be whoever wrote this! It wasted my evening.[/spoiler]
But this is my opinion, you do what you want.