I'm writing this after watching the 4th season.

The first one is a really interesting story, have a nice ending, and I think they should have stopped right there, but...

Then comes the second season, were they turn the story into a snowball. Ok, that wasn't terrible, it was cool to see what happens after with all the main characters, but...

They created a third season, witch is basically a follow up to the second season, forgetting absolutely that the series itself didn't needed a second season.

And now came the fourth one, where we see all the characters turned into caricatures, a ridiculous storyline and it seems they put all the stereotypes they could assemble in one season.

Really hope they forget the story and give it a rest. Only the first season really worth your time.