What's scary in this drama are not the so called monsters but the astonishing depicture of human nature. All the cast did a great job, to the point that ML and FL may seem the weaker ones (for me the most stereotyped and unchanging during the course of the story, but well played anyway).
If you are looking for an horror drama, maybe this is not for you (it's rather a splatter one); but if you want to watch a story about society, human behaviour and relationships in hardship, you won't be disappointed.