It's a lot of curveballs. There's the rich family with the deformed daughter and a son that can control minds that owns half the town including a medical research facility. The son and his cousin have a relationship that appears to be incestuous at first. There's a gypsy werewolf who develops an unusual friendship with the son and daughter, and those are just the obvious plot lines.
Between the werewolf, the medical research facility and the cousin of the family being impregnated by an angel, it's a lot to keep up with but it doesn't move so fast that you lose track of it all. And while it seems that by revealing the werewolf so fast they made the outcome obvious, they didn't. The series finale reveals a couple of major curveballs and a couple of cliffhangers.
It's hard to go into more detail without giving away too many spoilers. I'd go so far as saying get the one moth trial Netfix membership just to watch Hemlock Grove.
Besides it stars Bill Skarsgard Who happens to be the younger brother of Alexander.
I didn't get into the Vikings but if/when it shows up on Netflix I'll probably watch it. I think it was an interesting move for Netflix to produce it's own series. I'm hoping that it will be more than one season.