Walter in his lab in this clip from Fringe. It's courtesy of the episode "6B."
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"Our world is starting to come apart." Check out this promo for Fringe to see who says this and why.
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Fringe Season 3 Episode 14 Quotes

Peter: I've seen what the two of us together looks like, and it's beautiful.
Olivia: Peter, she's the one who took it away from us, not me.
Peter: And now? Who's the one stopping us now?

Peter: He wants us to spend time together.
Olivia: The three of us? (the song Feelings plays in the background)
Peter: No, just the two.