I'm very hesitant as whether to give this show a 5 star or not. The beginning of each season starts off very strong; excellent introductions of characters, story telling, and suspense building.
Subjectively, however, it's goes from a 5 star show to a 4 star. The ending of each season doesn't leave me satisfied. It's anti-climactic and the somewhat predictable demise of the villains just happens so quick. It very well could be the number of episodes weren't enough to tie up spending multiples episodes building up a character then having them killed in less than a minute of screen time on the last episode.
Anyway, it's worth the ride and worth waiting for season 3.