Wow, Etta showing up would have been incredible.

The answer to all of your questions is simple: Bell is batshit insane.

All I ask is that in Season 5, the writers put in a line about how Detective Amy Jessup fell into a vortex or something.

But it's not a happy ending. The observers come in, they take over, Olivia dies, etc. We've seen the future and it aint happy!

This is probably going to be the most polarizing episode the show has ever done. I personally loved it. I see it's faults, but there was so much sci-fi craziness going on that I didn't care. I also feel it was sort of tough for the writers because they had to make it work as a season finale as well as a possible…

In one of the first episodes of the season, Lincoln walked into that room and looked up. To the right, he saw a window with a clear blue sky. To the left, he saw a window with a cloudy sky and a zeppelin. So half of it exists on Earth-1, the other on Earth-2.

I think now that the show has been renewed, we'll see the other side again.

Will there ever be a rainbow?

I want to see them go all out in Season 5. Crisis on Infinite Earths style.

You would think that if future humans had the technology to send an entire civilization back in time, they would also have the tech to solve their environmental problems or at the very least the ability to colonize another planet/moon.

I really love that we got a real, concrete explanation for who the Observers are. An actual sci-fi explanation. I was a little worried they were going to end up being angels or something.

I also got an X-Files vibe. When they first saw the airplane lights, it even looked like a UFO.

If only they would have hired Airport Security to guard the wormhole between universes! We wouldn't be in this mess to begin with.

Yeah, that sort of bugged me too. And didn't one of the Observers see it in the parking lot when the two guys had that confrontation? Why didn't he just steal it then? And it's hard for me to believe that an Observer, who experiences past/present/future, would ever be able to "lose" something.

I wondered that too. Same thing happened between the Astrids.

What sort of made me laugh was that he stepped through the window to see what was going on outside. I mean, it's a window - couldn't he just have looked through it? Maybe his device has really bad reception and he has to be outside for it to work or something.

Olivia and Broyles looking at all the Observer photos tacked up on the wall was also a callback to S1. I believe the first episode.

"If this Olivia is doomed to die (and I think that's a big if,
given the generally tricky way the Observers have been used in the past,
and the outcome of tonight's episode), well, that would be sad, I
guess… But we do have reserves."

Charlie is on a honeymoon with Bug Girl.

They could stare at the camera and tell me to buy the car for all I care. As long as it helps the show stay on the air.