Plec told Entertainment Weekly that Stefan (Paul Wesley) will have "tunnel vision" when it comes to his plan to destroy the Original vampire.
"We get the sense that this guy, who used to be much more concerned with protecting collateral damage, now has no concerns about who might get hurt as he tries to get Klaus to back off," she hinted.
"[The hybrids] are contributing to the sense of unease that Elena and her friends have about living in this town, and Klaus is relishing everybody's paranoia, and Stefan is sort of like, 'No way, get 'em out. You're not gonna get 'em out? I'll get 'em out for you'. So Stefan starts going all Jack Bauer-Chuck Norris on them."
However, Plec added that Elena (Nina Dobrev) will be unhappy with the "extreme lengths" which Stefan goes to in an attempt to get rid of Klaus.
"His methods are not very much appreciated by Elena," she said. "Our characters themselves are asking this question: Is he good? Is he bad? Is his humanity switched on or off? If on, what the hell is going on? What's he doing? And the question of how Stefan is channelling all of his emotions into this rage makes him as much of a villain in his own way as he's been all season."
A recent report revealed that future episodes of The Vampire Diaries will see an "epic kiss scene" and the exit of a major character.
The show will return with a new episode on Thursday at 8/7c on The CW.
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