The aliens finally return this April in IDW Publishing's "X-Files: Season Ten" #11. "Pilgrims" is writer Joe Harris and artist Matthew Dow Smith's first story-arc designed specifically to deal with the classic alien mythology that was a recurring plotline through all nine season of the hit television series. Over the course of the arc, Special Agents Mulder and Scully, newly reinstated in the FBI, travel to the Middle East to investigate a terror attack only to discover something they thought they'd never see again -- Purity, or as it's better known, the black oil.

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Casey spoke with CBR News about bringing back the alien conspiracy, explaining how the black oil ties into everything, why he refuses to use ret-cons and why some plotlines are going to go untouched for now, just in case creator Chris Carter decides to pick them up for a potential "X-Files 3" film.

CBR News: Fans have been waiting since issue #1 for this, so how will your new "X-Files: Season 10" arc touch on the alien mythos that was at the heart of the show's nine seasons?

Joe Harris: We're going to be getting into the central "X-Files" idea that there is already an alien presence on Earth. That there are secrets that humanity doesn't know a lot about and there are forces out there swirling to uncover those secrets in order to horde, capitalize and benefit from them. The initial arc, "Believers," was really about resetting the deck. It was about a cult of half-alien characters that were hunting Dana Scully and the son she gave up for adoption, William. It was an opportunity to introduce all the characters and introduce the concept that there was a conspiracy centered on the alien plot to repopulate the planet Earth.

In this new arc, "Pilgrims," everything is up and running a little bit and we've been laying some clues about what's really behind the characters that have been coming back, what's up with the reemergence with some of the concepts related to the alien plot, like Purity, and in the new arc we'll see all those things kicked up a notch. We're going to thrust Mulder and Scully back into this alien world. Some old threats that they thought were dead and buried come back, and some new threats emerge. They're going to have to figure out what's really at stake for humanity and who they can trust and what's happening.

We're bringing back a major character people haven't seen in a while, too, that will make fans both delighted and disgusted in turn. I wish I could spill the beans on who it is, but all I can say is there will be a very polarizing reaction to his return. We'll also develop the neo-syndicate more, including advancing just exactly how the Smoking Man is walking around, considering we saw him get blown up by rockets in the series finale.

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"Pilgrims" is also set to incorporate the infamous black oil from the TV show, arguably one of the most popular aspects of the entire "X-Files" canon. How's it going to play in to this new arc?

We've been not-so-coyly teasing its return in the solicitation copy. It's vague, but it's not too hard to figure out if you're a fan. A new deposit of Purity, the black oil, is uncovered and this discovery ends up bringing the FBI to Saudi Arabia because of an attack on the largest oil field on the planet. Some Americans are killed in the attack, and since the FBI is the lead investigatory agency when Americans are killed overseas, they go to investigate. They end up discovering that there's a lot more than oil drilling at the facility. There's a lot more forces they end up having to deal with than just the Saudi government, too. Basically, there's something else going on under the sands in the Middle East.

We'll also deal with the idea that not all the aliens are bad, as has been touched on in the past. There's been this idea that there are rebels seeking to thwart the plans to recolonize the Earth. Some of the things that Mulder and Scully discover as the black oil is returned to the mythology is that some of the would-be alien colonists are not as advertised. Some of them just want to go home after many, many millennia buried under the Earth.

In your first arc, "Believers," Scully was hunted by a group of half-alien cultists called the Acolytes. Are these the same aliens that appear in "Pilgrims?"

They're separate groups, although we might see the Acolytes playing a role in this arc, as well. I don't like to keep too many things dangling, so we'll be at least touching on some of the stuff left over from the first arc. I like to believe that everything fits together into a tapestry.

So we might see Mr. X again, too?

I would love that. His presence ties into the mystery at the heart of the neo-syndicate. Similarly, we've seen the Smoking Man have difficulties. He's not quite himself. You may, in fact, see X at some point. He's certainly a person favorite of mine, but everything is not as it seems. I expect that if we see him again, it won't be his glory days.

One thing I'm trying to do is not use ret-cons. Instead, I try to find creative answers to bring people back without changing the past. A lot of people want to see these characters, but it's important to me to not act like everyone had a miraculous recovery to appear again. There has to be a creative purpose for these characters coming back. It has to fit into some over-arching plan that will grow fruit later.

One of the biggest and most welcome surprises of the series for me was opening up issue #2 and seeing Special Agent Doggett there. Doggett is easily one of my favorite characters, so I was a little bummed when he immediately went missing! Are there more plans in store for the character?

It's fascinating to me you say that. I think it's cool, 'cause I like him too. I love when people tell me they love Doggett. Although I remember when the show was out and everybody was like, "Fuck this guy! I mean, I like 'Terminator 2,' but where the hell is Mulder?!"

Stay tuned, though, he will be coming back in some capacity. I like writing him and I thought it was fun having him back in that brief scene. I had no idea what we were going to do with him after that, but I was glad he showed up. And you're not the first person to tell me they love Doggett, either. I'm shocked by how many people really, really like John Doggett!

I never understood why everyone hated him back then. It was probably just because he wasn't Fox Mulder. Whoever took that role was going to face a certain amount of fan backlash, no matter who they were.

Yeah, totally. I also think people found it hard to accept that he was going to play opposite Scully. People really resisted the idea of Scully having an on-screen connection with anyone other than Mulder. I feel that that manifested a little bit in Scully and Doggett's relationship on-screen, for the better.

When we spoke last year, you mentioned that the series would eventually address the fact that the alien invasion prophesied to occur in 2012 on the series finale didn't actually end up happening. Are we getting closer to learning the truth?

It's a delicate dance. I'll be honest with you, we're trying to leave room for Chris Carter to tell the story he really wants to tell with regard to the invasion and the next chapter involving Scully's son William. So I would say, "Not exactly." However, I would hope we wouldn't continue to evade it, either. It's really a careful orchestration when you're in our position. We don't want to step on any ground Chris Carter might want to explore in a potential third "X-Files" movie, not that I have any inside info on where that project stands or what it would contain. I just know that there is ground he really wants to cover. So we're trying to leave a bit of a wide berth.

Overall, what's the reaction been like from fans since launching "X-Files?"

I would hesitate to say it's unanimous, because a lot of people have a lot of strong feelings when it comes to "The X-Files." But by and large, it's been met with a lot of appreciation. I hear from people all the time on social media, at shows and at signings that they're really excited. They think we got the voices of the characters down, that they sound just like Agents Mulder and Scully.

"Pilgrims" begins in "The X-Files" #11, out this April from IDW Publishing.