Paul Wesley Paul Wesley

The Vampire Diaries' Stefan Salvatore is headed back down the ripper road, but this time will he be able to return from it?

"There will be a surprising thing that happens a few episodes in that will cause Stefan to turn the corner fully and really absorb himself in this darkness with absolutely no sense of conscience and no predisposed history of his prior empathy and his prior life as a 'good' so to speak," Paul Wesley tells "Damon, in comparison to what Stefan is morphing into, is a puppy."

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When viewers last saw Stefan, he had agreed to team up with the most powerful and dangerous creature to grace Mystic Falls, Klaus, in order to get the cure for Damon's fatal wolf bite. Stefan and Klaus (Joseph Morgan) are on the road in the Season 3 premiere, and time will pass before Stefan is reunited with girlfriend Elena (Nina Dobrev).

"Stefan is doing everything he can to not come face-to-face with Elena because what she represents is a part of him he's had to let go of," executive producer Julie Plec says. "[He's] reverting to some old behaviors and old problems that he has worked very hard to combat and it's a side of himself he never wanted Elena to see again."

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Wesley likens Stefan's taste of blood to a recovering drug addict using again, and says that, although viewers may not like the blood-thirsty version of Stefan, he's OK with that. "Not every character has to be likeable, [but] every character should have empathy.  I think viewers should watch Stefan and feel [for him], whether they agree or disagree with what he's doing."

As Stefan travels further towards destruction we'll continue to see different sides of him. At first, Stefan reluctantly follows through with Klaus' demands while secretly plotting against him so that he can protect his loved ones. Then, Plec says, "There's the Stefan who just can't stop once he gets started ... and then ultimately there's going to be the Stefan that doesn't care anymore and that's the most dangerous Stefan. When that happens that will take the most to recover from."

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With Stefan away, there will be plenty of alone time left for Damon and Elena. The two shared a kiss while Damon was on his deathbed, but more importantly, he finally sought redemption and Elena forgave him. What does their future hold now that they've come to a place of understanding — and possible more? Guilt, Plec says. "That's going to loom heavily over them. Damon is not one who likes to feel guilt or obligation ... so does he go back to his crazy, wild ways as a way of making a point that he feels no guilt for no man? Or is he being driven by his need to bring his brother back? Or does he say, 'Screw it, I'm going after the girl I love'?"

Plec adds that Damon starts to think, "Well hang on, I thought maybe I never had a chance with his girl because how could she love a monster like me? But hey if you stack a monster and a monster, I ain't so bad."

Elena, meanwhile, will also have conflicting emotions over the situation (just look at the latest promo!).  Katherine was onto something when she told her in the finale, "It's OK to love them both." As she turns 18, she'll start to soul-search and Plec says, "Although it's not very conventional ... she'll soon have to ask herself that question of, 'How do I feel about each of them and is what I feel OK? What it is about me that loves the way I love and who I love and what does that say about me?'"

Still, hope is not lost between Stefan and Elena. "That eternal love story between Elena and Stefan is something that I hope everyone always roots for, but they might not like him in the process," Wesley says.

Adds Plec: "The one thing Elena understands fundamentally about Stefan is that there's the Stefan who's a monster being lead by his own demons — the basic nature of vampirism — and then there's the Stefan that fought like hell to hold onto whatever part of his humanity he could hold onto — and that Stefan is worth saving."

The Vampire Diaries airs Thursdays at 8/7c on CW.

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