It's great. The first season starts off a bit slow, but once it picks up, it never really slows down. Season 2 is pretty much non-stop quality. Season 3 starts off strong as well, begins to dip just a bit in the middle (while still being very good), but picks it back up in the end. And the cliffhanger basically ensures that Season 4 will continue to be awesome.
It's not Twilight: the TV Series.
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