From J. Plec interview for EW.com:
Don’t expect Stefan to come out of the quarry unscathed. Plec hints that when he finally emerges from confinement, he’ll be both the same and drastically different. “There’s a little bit of a riddle attached to that which I can’t really expand on, but it’s going to be a fun ride for Paul Wesley to play as an actor,” teases Plec.
From C. Dries interview for ETonline.com:
ETonline: Which storyline do you feel is the most heartbreaking this season?
Dries: For me, it’s very obviously Stefan’s storyline. And yes, Stefan does have a storyline even though he’s trapped in a safe dying. It’s so beautiful.
ETonline: Logistically is it tough to write for a guy trapped in a box?
Dries: [laughs] Um … yes. For a while we toyed with the idea of showing Stefan once and then not seeing him again. But then we remembered he’s a main character on this show [laughs]. So we sat and wondered about the best Stefan storyline to tell, and I think we landed on a good one.
From C. Dries interview for Gather.com:
Stefan’s having a hell of a summer. Poor Stefan is going to be suffering for a while underwater. “The real big bad of the season is Silas, so he’s going to be integrating himself into Mystic Falls, and of course, Stefan, nobody knows he’s missing,” Dries previewed. “Everyone, as far as Damon and Elena were concerned, just thought he rode off when he was in the car with Lexi. …They were kind of like, ‘It’s weird that he hasn’t called, but…’ Stefan is going to deal with the repercussions of spending a summer or more in this hell. The storyline’s going to be pretty dark this season, but also really cool too. It’ll be a new Stefan.”
From Wetpaint Entertainment:
Caroline Dries: We have cool new mythologies that we’re introducing this season. So obviously, you’ve met Silas briefly at the end of the season, and so going into this season, we already know Elena’s a doppelgänger. Katherine’s a doppelganger. So we’re just like, “Why do doppelgänger exist?” And so now that we realize Stefan’s a doppelgänger, we kind of explore the deeper mythology of why does this weird phenomena occur. So that’s pretty cool. And that has ripple effects for all of our main three characters.
Does everyone have a doppelgänger?
JP: No. The mystery of how the doppelgänger was created and why and how often they appear and for what reason is something that we actually start getting into right away. And by Episode 3, we start laying a lot of the answers to that mystery out.
What Stefan? What’s happening?
JP: Well, poor Stefan has just been on the quarry floor in that safe, drowning over and over again all summer long. So he’s struggling, to put it mildly, and hopefully he won’t have to struggle for much longer because his loved ones will realize that he’s missing. But until that happens, he’s just screwed.
CD: So many seem to have a really heartbreaking story in the first episode.
JP: Yeah, it’s funny, in spite of being in the bottom of the quarry floor, the Stefan storyline in episode one is really moving, and keeps alive that sense of his strong feelings for both his brother and for Elena.