Fringe, Season 4

Walter:
I guess this is it.

Dunham:
[hugs Walter] Thank you for everything.

Walter:
[speaking of Colonel Broyles] Don't judge him. No one can be certain exactly what they're capable of, how far they'll go, to save the ones they love. I know this more than most. Keep an eye on this universe, will you? I've grown quite fond of it. [leaves]

Dunham:
See, I'm surprised that you're not going back with him.

Lincoln:
I told you I'd help find the people who killed your partner and mine. Until we do that, I'm not going anywhere. Look, it might not feel like it now, but it does get better.