First season is good, interesting and gripping.
The second season starts to lose it a bit with the same recurrent themes recycled and some repetitiveness in the dialogues.
The third season is almost un-watchable. With the same pointless dialogues made out of stupid metaphores played over and over, a chaos of worlds and times that mixes up and the same boring and tasteless acting by most of the characters. It seems that they run out of ideas and they are trying to milk it with extra characters.
Episode seven tried to explain the idea behind it but all it is a forced comparison with the most quoted and appealing theory out there: the Schoridnger's cat. It doesnt work and it doesnt make it easier to watch.