The Vampire Diaries' Paul Wesley: Stefan Is Screwed Up in the Head This Season

Paul Wesley has played several reincarnations of his Vampire Diaries character, from sensitive Stefan to Ripper Stefan and various shades in between. But at the start of Season 5 (Thursday, 8/7c, The CW), Wesley takes on his biggest challenge yet by playing two characters — a physically destroyed Stefan and his immortal and manipulative doppelganger Silas.

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At the end of last season, Stefan was leaving town to bury what he believed was Silas' body while also getting a fresh start away from Mystic Falls and the love of his life, Elena (Nina Dobrev), who is now dating his brother Damon (Ian Somerhalder). However, his game plan suddenly went awry when Silas transformed into his "shadow self" — a doppelganger of Stefan. He then staked Stefan, locked him in a coffin and threw him to the bottom of the river.

"Stefan is really screwed up in the head when he gets out of this quarry," Wesley tells TVGuide.com in the video below. "He has had all these torturous experiences and so now doesn't react the same way as he used to and he's not as malleable. He's definitely a different man."

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Before Stefan returns to Mystic Falls, Wesley will appear as Silas — except his friends and brother won't immediately know it's him. But it's not long before Damon and Jeremy (Steven McQueen) sense something is up — especially when this new "Stefan" has a completely different, aka cocky, air about him.

"Silas has so much pain and anger and hurt, but it's masked by a level of light energy and humor," Wesley says. "[He isn't] intimidated by anything and the world is his playground. He's 2000 years old and finds himself to be supremely more interesting and sophisticated. He doesn't feed on people, he thinks it's gross and primitive, so he manipulates people into cutting themselves and pouring their blood and then he drinks it; he's a little snobby."

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As Stefan suffers and Silas wreaks havoc, Elena's kindred connection to Stefan will prove stronger than ever, giving her a deep sense that something is seriously wrong. "When you were in love with someone, even if they're not in your life you have that connection with them; the love is still there whether it's romantic or not." Dobrev says. "When she finds out what he's been through it's not easy for her."

Ultimately, Elena, Damon & Co. will realize that who they think is Stefan is actually Silas, while at the same time Stefan will eventually emerge from his perpetually drowning state. As these two versions continue to co-exist, Wesley will play the two roles until the season's Big Bad is defeated — unless he isn't. As fans may remember, the last epic villain, Klaus (Joseph Morgan), was originally supposed to die in Season 3. When he became a fan favorite, his character remained on the series and ultimately landing a spin-off. What happens if Wesley receives the same adoration during his time as Silas? Executive producer Julie Plec tells us there's always a back-up plan.

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"Klaus is a perfect example because thank God the happy ending to that story is a spin-off," Plec says. "We didn't want to kill him because we liked him so much, but he was on the precipice of becoming a story vacuum if we weren't careful. Silas is the same thing. He is a villain and at some point the bad guy needs to be dealt with and vanquished, no matter how good they are. So we'll see. We definitely have plans to vanquish him, but we have an open mind to keep him around, it depends on the success of the storyline and the actor in both roles and, frankly, if there's more story to tell."

What does Wesley think about that prospect?

"I think what the fans like and what the fans react to is making Stefan dynamic," he says. "He's the hero and everyone wants to see the hero's journey and his fall and his great redemption and I think that's what it's all about. So if they can make Stefan dynamic continually then I don't know if Silas is necessary for the entire length of the show."

Watch Wesley talk more about Season 5 below:

The Vampire Diaries premieres on Thursday, Oct. 3 at 8/7c on The CW.

(Full disclosure: TVGuide.com is owned by CBS, one of the CW's parent companies.)