Interesting concept with a, more or less, decent execution. The sense of dread is definitely there. It's tense at times and it feels thrilling. The vampires feel ominous (specially since you don't know what they're are). Also, directing is pretty decent. There are some nice shots here and there.
As for the weak part, the characters are too flat. People die throughout this film, but, in the end, you don't really care because you don't know them. The only relatively…