Fringe 414 "The End Of All Things"

Now it is clear what are observers.

Last episode concluded at the scene captured Olivia and Nina. This episode go through with Olivia and Jones's dialogue about supernatural power, remembering season 1. Jones used Nina as hostage, lately found she was shapeshifter or something. Is this means true Nina is fully innocent? I'm not quite sure.

And then, with an advantage of knowledge, Olivia electrocuted one of Jones's fellows. Fake Nina had to reduce Cortexiphan not to recall Olivia's memory, I think.

In September and Peter's mind meld, September tell Peter that observers came from future so that they had less hair and not good at taste.
And it is revealed that creators not forgot about Henry. In fact, I don't recognize at few seconds.

This time Jones didn't separate from this world and another world. So his plan is advanced?

Peter thought Olivia is not Olivia, again. Hmm..