Wild how many low ratings there are. Everyone is saying there's plot holes and such but I took it as that woman's perspective... which obviously she doesn't see everything going on except for what is happening I front of her. I thought the acting was great and the reason she was able to stay so level headed almost through to the end was her previous drug abuse and surviving in an altered state of mind before. There was definitely some hit or miss things but I was intrigued the whole time and for the people stating it doesn't make sense trying to sacrifice the girl after a few hours... the guy in the beginning literally said it progresses quicker than normal sleep deprivation.. so honestly a good quick watch that definitely kept my attention!