Against all odds, "The Originals" is bringing Marcel (Charles Michael Davis) and Klaus (Joseph Morgan) back together... And all it took was an evil force targeting children, including Klaus' own daughter. With so many questions remaining about what this entity is and how our favorite vampires, witches and werewolves can take it on, there was no better place to go looking for answers than executive producer Michael Narducci.

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We spoke with Narducci about the secrets behind Season 4's villain, how Hope (Summer Fontana) has changed Klaus, and what "TVD" ending means for crossovers. Finally, we also asked Narducci, who departs as "The Originals" showrunner at the end of Season 4, about saying goodbye to a show he's been diligently tending since before it even started...

We've seen just how dastardly this new presence in New Orleans can be, and that it's targeting children -- including Hope. Yet we're still in the dark about the details. What can you share about what we'll be learning?

Years and years ago, Vincent Griffith was a witch who knew that he didn't want to be forced out of New Orleans because of the vampires. So when he found out his wife Eva was going to have a baby, he sought a means of gaining power. And by opening himself up to that desire for power, something gifted him with a book -- a very dangerous grimoire -- that seems to be written in his own handwriting and is filled with powerful spells of sacrificial magic.

He and his wife began to practice this sacrificial magic. They realized that the power was very overwhelming, and Eva got so caught up in it that she began to, as we explored in Season 2, kidnap children, and she was going to sacrifice those children. Ultimately, Vincent stopped her and tried to help her out, cure her. It didn't go well and she ended up being committed to an insane asylum for witches, which is where we met her in Season 2.

Now, all these years later, this dark presence, this evil spirit, this thing that got its claws into Eva Sinclair and Vincent, is now returning -- and we have seen at least one other person who has been affected by this, the gentleman who took the children in episode three, that Vincent and Marcel were able to kill. Just when you thought those children were safe, now we realize that no less a person than Detective Will Kinney -- a human, not a witch -- has taken those children back under his custody. Where is he going to take them? That's going to be what we explore in episode four.

But the idea is this spirit has a lot of followers -- not just witches. So you begin to wonder who else is involved in this: How big is this cult? What is on the other side of the cult? What is the thing these people are worshiping, and how dangerous is it? What will Vincent have to confront to do what he has vowed to do, which is protect his city?

Tying it to Vincent is interesting -- you can't help but wonder if he'll be holding himself responsible for what's happening, regardless of fault.

He does feel a sense of responsibility, even though he's no more guilty than anyone who's investigating any other form of alternative power. The moment he knew that his magic was getting out of hand, and that this power was tempting him to harm innocents, he pulled away.

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It was Eva who, secretly and unbeknownst to him, continued -- and escalated her efforts to gain power. I think what we have to consider if there are more Eva Sinclairs out there. There might be a city full of Eva Sinclairs out there, who might be wiling to make a deal with this particular monster. And that's a very scary premise.

Turning away from the scary for a moment, in the last episode we got to see a very different side of Klaus. He simply got to be a dad to Hope for a bit. As we move forward, will she continue to bring out his softer side?

I think so, absolutely! That is definitely what we want to explore. And I'll remind you, Klaus has had interactions with a child before. In the year 1820 he rescued Marcel Gerard, and decided to raise Marcel as his ward. I think Marcel's influence on Klaus was massive, and it changed him for a time... Until those two grew apart. It's fraught with conflict, and has been a great source of pain for both men.

Now, coming out of five years of captivity by the person he raised as a son, he's reintroduced to his seven-year-old daughter. And I can't believe that Klaus, somewhere in the back of his mind, isn't thinking, "I tried to raise a kid once and it did not go well. Now I really have to do right by this child -- I'm not going to fail her, I'm not going to let her down. What do I do? How do I make sure I don't make some of the same mistakes?"

We spoke to Charles shortly before the premiere, and discussed the possibility of Marcel and the Mikaelsons working together -- how the right foe could bring that about. As we're clearly facing an evil that could do exactly that, can you talk about how that dynamic has changed after these five years?

Marcel hates Klaus, hates the Mikaelsons, because they allowed Davina to die -- and basically, Elijah executed Marcel. And I think Klaus is furious at Marcel for stealing five years of his life, and because Marcel bit Elijah and Kol. Marcel sentenced his brothers to death, and then sentenced him to five years' captivity -- maybe longer, if Klaus hadn't been able to escape.

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Now we have a world where these two one-time friends who are now enemies are exposed to the reality that something is out there, and it's not going to let them go. It's not going to give them peace. It's beginning by attacking the most vulnerable members of their respective families -- it's attacking the children of New Orleans, which concerns Marcel. He's always, since the beginning of our show, had a rule: No kids. Marcel will not allow a child to be harmed, because he himself was a child who was abused. And Klaus realizes that the thing he loves most is his little girl, and she has been targeted by this monster. These two mortal enemies have a mutual enemy.

We haven't seen it yet, but 'The Originals' gets to have Matt Davis appear this season as Alaric. Is it easier to formulate how to bring 'The Vampire Diaries' characters in, with the jump in time on 'The Originals' and 'TVD' having come to an end?

The biggest hurdle in having crossovers was the respective schedules of the two shows. In other words, if you have Matt David come onto "The Originals," he has to shoot those days -- but he also has an obligation to shoot whatever his role is on "The Vampire Diaries." Now that "The Vampire Diaries" is no longer shooting, we do have a greater freedom and an easier schedule to bring those actors onto our show. So I think crossovers might be something you can potentially see more of in future seasons of "The Originals."

This season we still had to navigate the problems of, "Oh, Matt Davis is shooting X, Y and Z. We need to shoot A, B and C." So it was a little tricky, but we managed to do it. And because of the five-year time jump, we're on a different timeline -- we didn't need to say why, on "The Vampire Diaries," Alaric was free. We can just get a sense that he had a free moment and he came to play ball with the people in New Orleans.

Lastly, you announced in January that this was your final season on "The Originals." You've been there since before the beginning, so what has the process of saying goodbye been like?

That's a great question -- it has been, to be honest, pretty emotional. I have a great respect and admiration for our actors, I truly adore our crew, I loved working with all of our directors and our two directors of photography, who are amazing, and all of the different producers, heads of wardrobe, props -- all of the different people I've had the chance to work with and love so much.

It's a difficult thing to move on. I'm a huge, huge fan of our writers and I think one of the things that makes it easier is knowing that I will move on, but there are still really strong writers on staff -- and I know that with Julie [Plec]'s guidance, there's going to be some amazing storytelling in Season 5, which I'm still very hopeful we'll have the chance to see.

"The Originals" airs Fridays at 8 p.m. ET/PT on The CW.

Posted by:Chris E. Hayner

Chris E. Hayner is equal parts nerd, crazy person and coffee. He watches too much TV, knows more about pro wrestling than you do and remembers every single show from the TGIF lineup. You may have seen him as a pro-shark protester in "Sharknado 3." His eventual memoir will be called "You're Wrong, Here's Why..." TV words to live by: "I'm a firm believer that sometimes it's right to do the wrong thing."