DON'T TRUST THE BAD REVIEWS!!
The film delivers perfectly on its very subject which is dark and dehumanising post apocalyptic survival. Everything spins out of order slowly and you realise how people who were originally good and helpful go mad and succumb to a mob mentality after a few months of an endless rut.
Take it with a pinch of salt and don't watch it if you're faint hearted because it'll shock you to the core with its realism which apparently all the negative reviewers are not prepared for.
Life is not a Disney movie!