This isn't really a horror film, at least for slightly over half of it. There are definitely some hints at some interesting themes that the film doesn't really touch on as thoroughly as it probably should have. There's the whole 'playing god' issue about bringing people back from the dead that you maybe should not have brought back. I think the film plays, a bit, with the religion vs science aspect but, again, much like any interesting theme in the film, does so in a fairly straightforward and simple manner. It's every science vs religion argument you have ever seen. The film has some pretty cool visuals, like the entire nightmare sequence that Zoe has throughout the film. I did like how they incorporated it into the story and how it's something that plays out throughout the 'narrative.' The problem is exactly that, that there's pretty much next to no narrative once Zoe dies and they have to bring her back with the serum. Once this happens, it's off to the races with the 'slasher' part of the film. It's not really a traditional slasher in the sense that it's really that violent, it's actually very tame all things considered, I just mean it in the sense that everybody's gonna die and they have a very short period of time to do so. It might have worked if you cared about the characters heading into Zoe's change, if you will, but there's next to no character development past Zoe and Frank being married, Zoe's recurring nightmare/childhood memory, Niko having a crush on Zoe, Clay being kind of a dick and Eva being the camerawoman. That's pretty much the extent of all the character development in the film. So, to no one's surprise, you didn't really care about anyone when the shit went down. It's not that the cast isn't good, because as far as horror goes, this is a pretty damn solid cast. I thought Olivia Wilde was actually pretty damn good as a horror villain, if it can be called that. I don't know, just the way her body language and how she acted actually really worked and added something to the film that improved it much more than just your basic horror film. It's not that I found this film to be bad, in the least, it actually has more on its mind that your regular horror flick, it's just that it didn't properly make use of its interesting themes. I found the film to be watchable, at best. Might not have been very good film, but it's at least watchable. It's not really something that I would recommend it, but I don't think that it's nearly as bad as both the critics score on Rotten Tomatoes or the audience score on here. I'm not saying it's good, but it's better than the scores would imply. However, with that said, I jsut think that there's a lot of wasted potential here with what seemed to be, on paper, to be an incredibly interesting concept that was used on what ended up being a substandard horror flick. It is what it is, unfortunately. Good idea, shoddy execution.