The absolute best, it was such an overwhelming acting, and all characters had so much depth, everything is amazing! It's heavy — the constant "rated 18" on the left top corner ain't there for decoration —, but not meaninglessly, it is not only used in the right amount to avoid being a gore-fest, but it is actually necessary for the story, all the violence is also very satisfying as it gives you time to dislike the characters. It 's greatness, true greatness, what a show.
The emotional weight it puts on you is heavy on its own as well, it's not a simple story, the story never stops deepening itself, on the present AND on the past . Also, the child actors? Insane job. Not insane for a kid, for any age, they did such an amazing job. The show is, there aren't enough adjectives to explain this. Perfect, no flaws.
Extremely coherent as well, there are no plot holes, you might think "this would never happen" but it's justified by the characters personalities, they build everything in a way that although it might seem unthinkable, it fits perfectly with what we already know about each individual and the whole of the story, so really, not one single thing I could complain about on this one.