Nina Dobrev Nina Dobrev

Mystic Falls fans, you're gonna want to see this.

In The Vampire Diaries' third season collection — out on DVD and Blu-ray today — we're getting some juicy insights into why Stefan went so dark last year. In one of the extras, entitled "Stefan's Descent into Darkness," both executive producer Julie Plec and star Paul Wesley discuss taking the character from Elena's lovey-dovey, plasma-denying beau to cold-blooded S.O.B. And it turns out, the idea to jerkify the guy was Wesley's! Sort of.

Check out what they have to say in this exclusive clip and don't forget to grab your copy of The Vampire Diaries on DVD and Blu-ray. (Also, could Plec be any cuter, typing away under her headphones?)

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