Warning: The following article contains major spoilers from Thursday’s season finale of The Vampire Diaries. Proceed at your own risk!

Thursday’s season finale of Vampire Diaries delivered several juicy twists — Stefan is Silas’ doppelganger! Katherine’s human! Jer’s alive, but Bonnie’s still a ghost! — and left us with even more burning questions. Is the newly mortal Kat about to get killed? Will no one notice something’s off with Stefan? And is Tyler finally going to come home?

TVLine went to executive producer Julie Plec to get answers on that and so much more.

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TVLINE | What’s Silas’ agenda as Stefan? Is he going to be sticking around town for some purpose?

I can’t say whether he’ll be sticking around town, although I can say that he’ll definitely be coming back to town when we get back into the next season. His agenda has always been to cure himself, to get rid of the other side so that he could then die and pass over and find peace. That will remain his agenda. The question is: How will he go about it? Everything he meant to do this year blew up in his face.

TVLINE | Can he really fool everyone into thinking he’s Stefan?

He’s going to give it a good college try. He is, after all, psychic, as well. So he can get inside people’s heads and make them think whatever he wants. It’s not like we’re going to play an entire season of The Parent Trap. [Laughs] But there will be some funny times right at the beginning of the season.

TVLINE | Now that Katherine is a human – and given that she’s pissed off her fair share of people in Mystic Falls – what’s to stop everyone from killing her?

Absolutely nothing is going to stop everyone from trying to kill her. That’s what puts her in a pickle that is going to have her seeking out protection from unlikely sources.

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TVLINE | With Stefan gone, Damon with Elena, and Klaus and Elijah on The Originals, who is left to care about what becomes of her?

[Laughs] That’s the realization she comes to over her summer break. “Oh, boy, did I screw up, and now my chickens are coming home to roost.” She’s definitely going to find herself on the wrong end of a lot of vendettas.

TVLINE | So Nina [Dobrev] will be playing two characters again for a pretty significant portion of the next season?

Yeah. We’ll definitely see a great storyline with Katherine as a human, and a great, fun one with Damon and Elena trying to make their relationship work as she heads off to college and starts her new life.

TVLINE | Speaking of, why Damon? What were you hoping to get to explore in Elena choosing Damon?

Damon’s a character who’s been driven by feeling like he’s not worthy of love. Now that he’s on the receiving end of that love, what will that mean for him? And where will he have to make changes in him, in his behavior? Or will he still be, “I am who I am. You love me for who I am. I’m not going to change for you”? It’ll be a fun dynamic to see him either trying to exercise restraint or not being able to exercise restraint in the name of love of this girl, especially as he’s got a new houseguest. He’s [living] with Jeremy Gilbert as Elena goes off to college.

TVLINE | It seemed like Caroline and Tyler are poised for a reunion. Will Michael Trevino be back next season as a regular?

Michael Trevino is still under contract. When he’ll return, we can’t say yet. He is going to have the opportunity to return to Caroline’s life in Mystic Falls. The question is, will he want to take it, given everything he’s been through since he’s been gone, which will be fun for us to learn — like what kind of life he’s been leading on the run.

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TVLINE | That last scene between Caroline and Klaus was so loaded with emotion and potential. Is there any chance at all of having Caroline move to The Originals? Or was that the capper on ‘Klaroline’ for now?

It’s not the capper, per se. We’ll have to be more judicious with the moments between them. We’ll see. Klaus has a long journey ahead of him. He’s got a very, very, very long road toward being a redeemed character. He hasn’t exactly been a peach. Even when he does nice things for Caroline, they don’t necessarily offset all the nasty things he’s done to her and all her friends. So as Caroline grows up and goes to college and experience a new phase of her life, we’ll see if she is still drawn to him and if he’s making the kind of changes that make her want to have him in her life at all.

TVLINE | Bonnie is still a series regular, so how does she fit into the scope of the show with only one person being able to see her?

She fits very much into the scope of the show as she tries to deal with the fact that what she thought maybe wouldn’t be so difficult actually is. The absence of physical touch and physical connection with the boy that she likes, just that alone makes her feel really distant. We’ll get to see her more in her own life a little bit as she tries to figure out ways to keep her secret — [and] also stay on top of her friends and what they’re doing and if they’re safe.

TVLINE | I’m surprised you didn’t find a way to keep Alaric (Matt Davis) around.

[Laughs] Put it this way, I was all on board with that pitch. I think it felt like if we kept everybody that we loved, we’d have an entire, new, double ensemble of series regulars.

TVLINE | Now that Katherine’s human, can Klaus use her to make more hybrids? Is that something he might be concerned about on The Originals?

Given his experience with his hybrids, he might be a little gun-shy about creating another army that could potentially be used against him.

Vampire Diaries fans, keep checking TVLine for lots more scoop about Season 5!