'Evil's Mike Colter, Aasif Mandvi and Katja Herbers on the Show's Series Finale and Legacy (Exclusive)

The fourth and final season of the psychological drama will begin streaming Thursday, May 23.

It's time for one last round, Evil fans, and the best is yet to come. The fourth and final season of the psychological drama will begin streaming on Paramount+ this week, and series stars Mike Colter, Katja Herbers and Aasif Mandvi tease that viewers have a lot to look forward to.

Billed as a psychological mystery, Evil aims to examine the origins of evil along the dividing line between science and religion. Season 4, which was originally announced in July 2022, consists of 14 episodes that follow the cast as they investigate the origins of evil and the church’s unexplained mysteries including demonic possession. 

"Kristen, David and Ben continue to assess cases that involve wayward technology, possessed pigs, demonic oppression and infestation, a dance muse conjured by alleged witches and an evil relic," the official description of the new season reads.

In February, it was announced that season 4 would be the show's final season, and production was given four bonus episodes to wrap up the story. Colter tells ET that show creators and writers, Robert and Michelle King, took that time to use "the best parts" of what they originally intended for future seasons to create a series finale. 

"They like to have time to really process where they're gonna go and I don't think they like to be rushed," Colter adds. "[When] we found out we were coming to an end, they had a few months, and I think Robert had to come up with the best parts of what he had intended on doing for the next two seasons and just touch on some things and, at the same time, leave it open. Leave it somewhere [between] a fulfilling ending and still not shut the door completely."

"So it was a really hard ask for him, but I think he did a great job," the Marvel alum says. "There were some things about the four episodes that made me think, 'Oh, if we had 20-something more episodes, this is what would have been seen from our characters.' So it's a great place to be in, and Robert and Michelle and their writing staff did a great job, so kudos to them."

Mandvi chimes in that "some loops have been closed" enough to give viewers closure without completely shutting the door on possible continuations.

"I think what makes our show so interesting is that there are some things that are just always going to be unanswered and I like that about the show," Mandvi says. "Like, it's not all neatly wrapped up in a bow because there are so many things in the show where you just go, 'Well, I don't know, we have no idea,' so I think that is nice that some things have been wrapped up and other things are not."

"What's also nice is that you do get a sense of like, 'OK, where are these characters now? Where do we leave them?' and we leave them in a specific place," Herbers says. 

Season 4 will also include cast members Michael Emerson, Kurt Fuller, Andrea Martin, Christine Lahti, Brooklyn Shuck, Skylar Gray, Maddy Crocco and Dalya Knapp.

It's leaving such an amazing cast that Mandvi says is the true downside to ending the series' run.

"The honest truth is in this business it is so hard to get a job where you get to work with amazing people -- the creators, the actors that you get to work with and other people," he tells ET. "To get to work with really great material and with really great people and to do it for four seasons is a rare thing, and I don't want people to think that we're not grateful for the fact that we got to do this amazing show and our amazing work."

Evil on CBS: Mike Colter as David Acosta and Katja Herbers as Kristen Bouchard - Elizabeth Fisher/CBS

He continues, "I'm so proud of the work that we did and for you all to see it on Paramount+. I'm really grateful for the fact that we got to do this amazing show."

The stars are also especially grateful to their fans, whom Mandvi points out has "grown over the years."

"I noticed after season 3 [that] we have people who are really, really attached to this these characters and the show," he gushes.

Colter agrees, adding, "We've had a really good fanbase I'd say, even since the first season... I know this is a show that we really take pride in and we like the fans because it's a show that when you're watching it, you have to peel back some layers. It provokes thought, it provokes discussion [and] you have to pay attention. It's not something you play in the background and do other things, so I really feel connected to our Evil fans. I [have a] special spot for them."

The thought-provoking storylines are a huge part of what Colter says will go down as the show's legacy. 

"I think what we've done onscreen in terms of the stories we've told and the worlds we've explored, I think it's just gonna make people [want to watch]. It feels like we're still being discovered and that's the fun part about the show." he tells ET of the show being able to draw new crowds as it joins streaming platforms.

"I just feel like it's nice to be able to bounce around and maybe find new audiences from time to time and that's a really cool thing about the platforms and about living on streaming; that we can just trickle around and grow our audience and also be introduced to people years later who are just like discovering us for the first time and that's nice," he adds. 

Herber notes that Evil is a show that "doesn't really compare to any other shows." That uniqueness draws in people who are curious about what could be explored in the series, she points out.  

"It's a very unique show in the genre that we live in," Mandvi adds. "And I just feel proud that we did such amazing work. We just always feel like whenever anybody watches it, you're not embarrassed. Like if people even watch the show five years from now, you're not going like, 'Oh my god, that show,' you know? We're just always gonna be really proud of the work that we did and even watching it."

The final season of Evil begins streaming on Paramount+ on May 23.