Ian Somerhalder and Paul Wesley

Is The Vampire Diaries' Damon Salvatore getting soft?

Ordinarily, we would have expected bad boy Damon (Ian Somerhalder) to move in on Elena (Nina Dobrev) while her true love — and Damon's brother — Stefan (Paul Wesley) was locked away in a tomb. So why didn't he?

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"There is a bit of a bonding moment that's happening with those two," Somerhalder told TVGuide.com during our visit to the set. "One would think ... that Damon is flying high and really ecstatic about that. Maybe six months ago, yes, he would be over the moon, but I don't think so anymore."

Executive producer Julie Plec adds that the sometimes strained bond between Damon and Stefan is crucial to the show.  "The power of the brotherhood between these two in times when they're living their lives the same, making the same heroic choices, or times when they're on opposite ends of the fight — that's the weight of the show," she says.

Even though Damon has threatened an eternity of misery on Stefan for making him turn into a vampire, Plec says will continue to continue to explore both sides of the brothers' love-hate relationship until the end of the series.

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"I love this idea of the two brothers, whether at odds or as partners, [taking] us all the way to the end," she says.

Watch our part 1 of our interview with Somerhalder below and check back every Thursday for a brand-new exclusive video from the set.