Vampire Diaries Celebrates 100 Episodes With Mind-Blowing Shocks -- and Katherine's Demise?

Vampire Diaries 100th episode SpoilersA former vampire on her deathbed, a recently broken up couple, blasts from the past and a whole lot of surprises.

There’s a bit of everything in The Vampire Diaries100th episode, airing this Thursday at 8/7c on The CW.

“There’s a couple good doozies between familiar faces that might show up and storylines that might be resolved in ways that fans thought they’d never be resolved,” teases executive producer Julie Plec, adding to watch out for “relationship moves that might really blow people’s minds.”

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Plec and fellow EP Caroline Dries set out “to have a little bit of fun” writing the momentous hour, Plec says. “You want to be 100 percent true to the story at all times. But in this episode, we let ourselves take a few extra nostalgia liberties so that we can celebrate some faces from the past, remember some moments from the past and make it a big party for everybody that was making it, as well.”

While the 5-year-old series celebrates a milestone offscreen, its characters host a vigil of sorts for the show’s villainess. As Katherine Pierce lies dying from old age in the Salvatore mansion, Elena and her friends take delight in toasting her demise.

“There’s a lot of people amongst our heroes who’ve been waiting for the day that they could watch Katherine Pierce go off gently into that good night,” previews Plec. “There’s a strange celebratory element to it, which granted, is a little insensitive, but as they start going through all the terrible things she’s ever done to them, it seems a little bit merited.”

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But Katherine wasn’t always a master manipulator and schemer. As the episode flashes back to the night she gave birth to a baby girl, “We’re really going to have an opportunity to understand Katherine in a new light,” says Candice Accola. “It’s a really great look at this character.

“If you really look at it, she’s the root that started this whole [story],” the actress continues. “The only reason Stefan stopped in Mystic Falls was because he thought he saw Katherine. The only reason Damon returned to Mystic Falls was because he was looking for Katherine. The only reason Caroline is a vampire is because of Katherine. The only reason Damon and Stefan ever became vampires was because of Katherine. And Elena is her doppelganger, so all brings it together. We’re really going to get to know the root of this group in a new light, and we’re going to learn more about her, and what she’s going through as a human.”

However, one person sympathizes with — rather than takes pleasure in — Katherine’s plight. “Stefan is having a more bittersweet reaction to it,” reveals Plec. “He’s been as victimized by her over the centuries as anybody else. And yet, he can’t help but feel compassion for this woman, this survivor, who has reached the end of the line.”

It seems something’s gotten into the younger Salvatore, because he even finds himself playing peacekeeper between his brother Damon and his new ex Elena. In separate moments with each of them, “Stefan actually tries to help them talk through what happened [in their split] and why and help them each understand it,” says Plec.

“In a strange way, Stefan is actually being a good friend to both of them in this episode and helping them come to terms with what it is Damon and Elena actually want from each other and whether their relationship is over like they think it is.”

But back to those doozies. With so many big twists and surprises promised, one can’t help but wonder what the viewer reception will be like.

“I definitely think the fans are going to lose their minds,” replies Kat Graham. “I think the fans are going to be in ecstasy when they watch it… There are some things that happen in the 100th episode that are going to make a couple people stand on their couches and scream at their TV, ‘Yes, yes, yes!’”