"I, too, attempted the unimaginable, and I succeeded... And since then, not a day has passed without me feeling the burden of that act." - Walter Bishop, "White Tulip," Fringe
I don't know where to start with Fringe, I love it so. It isn't perfect-- anyone who's seen the pilot episode can tell you that much-- but when it's good, it freaking shines. Symbolism. A detailed mythology. Round, juicy story arcs.
It took me pretty much the entire first season of the show to truly care about the characters. I didn't dislike the show, but it didn't hit me until the second season got rolling that I was totally and utterly invested in the characters and their fate. Now that I've watched the first season again, I think this is because, as a viewer, I developed an attachment to the characters at about the same rate as they developed attachments to each other. Their relationships build rather slowly despite the weird and creepy things that happen to them. I don't know if this was intentional on the part of the writers, but it feels like you're part of the rag tag team forming in front of you, and you can almost miss that it's happening until shit goes down and you suddenly realize that you care what happens to everyone else.