When the Show Jumped the shark
I think personaly that when they started teasing in season 2 where the show will go with the whole Walternative Parallel Universe stuff it found its own voice.
Because in the beginning it just felt like a modern adaptation of the X Files, which isn't bad even if we already had that with Dark Skies in the 90's.
The problem i had is that many parts of the plot elements like the one surrounding Peters true "nativity" and Walter involvement became too Soap Opera'ish.
And one major flaw was the whole last season which felt like if they rushed 3 seasons in 13 eps plus tje sfx, sets, lighting was horrible, it sadly looked from the first to last minute cheap and like a Set.
To be honest i didnt even finish the Show i still have 5 episodes left but i lost the interest in the Show which is sad because after the countless rewatching of The X Files back then i felt in love with Fringe when it aired until season 4 came on and i slowly began to disliking it.
Is the final any good? Or is it a cliche happy ending with Peter and Bishop happyly walking down the Sundown hand in hand