After three seasons of holy missions with often unholy results mixing science, religion and the truly outrageous, “Evil” is closing up shop the only way it could – with more demons, some witches and an antichrist baby.

“There's still so much to talk about with evil in the world,” says director Robert King, who created the horror-tinged, darkly comic Paramount+ drama (streaming Thursday, then weekly) with his wife and producing partner, Michelle King. “It feels like a novel that you're not going to write the last three chapters. But we're thrilled with what we got, and it will have an ending.”

“Evil” concludes with 14 final episodes featuring priest David (Mike Colter), psychologist Kristen (Katja Herbers) and tech expert Ben (Aasif Mandvi), who work for the Catholic Church investigating potential supernatural occurrences. The accessors have tackled everything from botched exorcisms to malevolent Internet videos, but they now face new cases involving possessed pigs and a particle accelerator that might also be a gateway to hell.

New 'Evil' season mines real-life science for onscreen horror

For the fourth season, the Kings leaned into uncanny mysteries of science and technology, especially artificial intelligence, to gin up scares. “We think of science as having so many if not all the answers, when in fact so many of these answers open more questions,” Robert King says. “Are there ways in which what the church calls demonic are good for us? Dante talks about muses; what are they? If they're real, is there a demonic element to them?”

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The last four episodes are “very much focused on the characters and seeing where these people end up in their lives,” says Michelle King.

And unto them, an antichrist baby will be born (but not Damien)

In the third-season cliffhanger, Kristen was shocked to learn out one of her eggs in storage at a fertility clinic was stolen by the villainous Leland (Michael Emerson), who works for the secretive group of demonic houses known as “The 60." It was used to conceive a child via surrogate using Leland’s sperm. (Oh, and Leland plans to raise him as the antichrist.) The new season picks up right where it left off, and rather than being upset, Kristen lets out a playful giggle and warns Leland that being a single parent is going to be a nightmare.

Robert King says they wanted to go in a different direction from, say, Damien in “The Omen” and focus more on real-life parenthood. “Infants that everybody thinks are so beautiful and natural and so cute and Anne Geddes-like darlings are not ever – they're terrors and horrors,” he says.

Adds Michelle: “We explore the idea of parenting and how much is predetermined, how much magic is there in love and baptism. Is that enough to erase evil?”

Katja Herbers' Kristen dreams of a normal existence

But there’s a lot going on for Kristen underneath the laugh, Herbers says. “That kind of neurotic or chaotic energy is some of my favorite material to play,” she says. Over the course of the series, Kristen’s “been messed with so much, and so much has happened to her,” from struggling with her marriage to Andy (Patrick Brammall) to questioning her own atheism while witnessing the most bonkers situations.

“The saving grace for Kristen in terms of normalcy is (her) four girls,” Michelle King says. “Regardless of the craziness that she's experiencing in her job, they're just doing adolescent girl stuff that ties her to reality.” Herbers loves that Kristen is “a mama bear” and has “such a loving big heart toward her children.”

Will David and Kristen ever be a couple on 'Evil'? Stay tuned!

Herbers also pulls double duty on “Evil” as the demon succubus Kristen, who started visiting David in carnal fashion last season following his awkward kiss with real Kristen. “She loves this guy, and she wants to be loved back and she's not always successful,” Herbers says of her demonic doppelganger.

As for the strong feelings and somewhat forbidden “will they or won’t they?” attraction between David and Kristen, “that is something that we will address” by the finale, Herbers says. “We won't pretend like nothing ever happened.”

But Colter doesn’t know if the audience will ever feel a sense of closure with those two, “at least on onscreen where the audience goes, ‘OK, that's exactly what this is and we can define it.’ The fun part is the journey.”

On 'Evil,' Mike Colter and Andrea Martin are believers of different stripes

David was also visited in the third-season finale by a Black female angel with a cryptic warning that bad things are coming. Her appearance “puts a clock on what the assessors are doing” and adds a sense of urgency to foiling the dark forces wanting to “bring mankind to its knees,” Colter says. 

David also fosters an important relationship in the closing chapters with Sister Andrea (Andrea Martin), a wise nun who wacks demons appearing only to her with her signature shovel. “If he's Luke Skywalker, she's Yoda,” Colter says.

While David has visions that he’s not sure are from God or something else, the sister “truly trusts what she sees,” Robert King adds. “We just like the idea of playing with what level of supernatural is there in the world, and if there is none, then how do you interpret what David's seeing and what Sister Andrea is seeing?”