SPOILER WARNING: This story discusses major plot points in Season 1, Episode 6 of “Moon Knight,” currently streaming on Disney+.

Throughout Marvel Studios’ “Moon Knight,” it’s been clear that the titular superhero at its center, played by Oscar Isaac, was contending with a profound issue with his mental health. Namely, his dissociative identity disorder had split his psyche into two people: Mark Spector, a hard-charging American mercenary, and Steven Grant, a mild-mannered British gift shop employee.

Savvy viewers of “Moon Knight,” however, have picked up on hints about Mark that fans of the Marvel comic series already know:  Mark’s mind harbors a third identity. And in the final scene of the (possibly) final episode of “Moon Knight,” audiences finally got to meet him: Jake Lockley. In the comics, Jake is a street-wise cab driver, but on the show, the audience comes to suspect — after Mark or Steven has blacked out when their life was in mortal danger — that Jake is capable of blistering acts of overwhelming violence. It’s not until the post-credits scene, though, that Jake finally shows up. He extracts Ethan Hawke’s Arthur Harrow from a psychiatric hospital, dumps him inside a stretch limo and kills him on behalf of the Egyptian god Khonshu. End of series!

Or is it? Marvel recently referred to the episode as the “season finale” of “Moon Knight,” not the series finale. Beyond Jake’s introduction, we also see Mark’s wife Layla (May Calamawy) become a superhero in her own right, as the avatar of the Egyptian goddess Taweret. According to Marvel, Layla’s superhero name is the Scarlet Scarab, taken from a male superhero introduced in 1977 (and killed off in 1982), and she is officially the first Egyptian superhero to occupy the Marvel Cinematic Universe.

All of that suggests a wide-open future for Mark/Steven/Jake and Layla — something Egyptian filmmaker Mohamed Diab, who directed the first, third, fifth and sixth episodes of “Moon Knight” — definitely hopes to help make happen. He talked with Variety about bringing Jake to life, why it was so important that Layla become a superhero and why he is proud that “Moon Knight” has zero crossovers with the rest of the MCU.

Did you know you wanted to end the show by introducing Jake Lockley?

Everything you see in the show is a trial and error, a process that we all went through. There were so many endings — like, not completely different endings, but just, let’s stop here, let’s stop here, let’s stop here. I think maybe the third or fourth draft, everyone knew that this would be the very last scene. But how much of Jake we’re seeing is something that we discussed for a longer time. I think we made the best decision. Everyone wants to know more about Jake. But if we would have introduced him in the show without really giving him the time to develop and be a full character like Mark and Steven, it wouldn’t have been fair to him. I think now we opened the door. If there is an expansion one day — which I hope there is, which I don’t know that there is — I could be a part of it and Jake can have his time to shine.

Well, Oscar Isaac was up front that he approached “Moon Knight” as a contained story and that he was wary of being tied to the MCU beyond it, given his experience with other franchises. But the Jake scene certainly suggests that there is more story to tell.

If you ask me, I would tell you that “Moon Knight” is here to stay. He’s an interesting character. If you are Marvel, I think the smart business decision is to keep him. The only thing is, Marvel is not traditional. If you succeed, it doesn’t mean you’re gonna get a Season 2. By the way, I’m kept in the dark. I have no clue. I’m just thinking as a businessman right now. But I think they’re going to stay. Maybe it’s going to be a film. Maybe it’s going to be a journey like what happened with “WandaVision.” I wish one day, if there is an expansion, I would be a part of it. We ended in a way that feels like a beginning. You see Mark and Steven becoming a new dynamic, the two of them in one body. We see Jake. You see the Scarlet Scarab, who could be a superhero or not. Very interesting stuff.

The series does play with the idea that all of this is in Mark’s head. Do you feel like the show ends with a definitive answer to that question?

My answer is this is a show that needs to be watched once and twice and three times. There’s so many clues. It’s not clear what’s real and what’s not. For example, we saw his brother drawing a fish. So if this is the reality, then how come that Steven had a fish with one fin, too? What inspired what? It’s a loop. And I think a lot of clues are like that.

Did you discuss the idea of having the show definitively exist just in Mark’s head — to truly have it be like a superhero story of the mind?

I always wanted it to be open. This is funny: I always told Kevin Feige, I want to have an ending when we discover the whole MCU is in his head. So it’s an open question.

You also introduce Layla as the Scarlet Scarab in the finale. How did that come about?

First thing, I want to give thanks to the writers who created the idea of Layla being an Egyptian. When Sarah [Goher], my wife and producer on the show, and I came along, we helped develop the character as Egyptians. When May came along, she became Layla’s biggest ally. The most important thing for us wasn’t just the idea of a superhero, but the idea of making her completely the opposite of every trope about Arab woman as submissive or weak. I’ve directed three movies: women in my movies are completely fierce and strong — like my mom, my sister, my wife and my daughter.

As a superhero, we knew that this is going to be historic. My daughter, when she was five, she wanted to straighten her hair. I had to take her to Disneyland and tell Princess Elsa and Anna, “Please tell her that her hair is beautiful.” She never saw anything on TV that looks like her. So today, seeing Layla, you don’t know what that means to people who look like us. It’s very important. “Moon Knight” is becoming a national pride in Egypt. People treat it like the Egyptian “Black Panther.” They love that behind the camera, there are Egyptians; in front of the camera, there are Egyptians. There’s Egyptian music that the world is enjoying. They believe in themselves. They believe they can do anything right now. I’m so proud of that.

Did you always know that Layla was going to be the Scarlet Scarab, or did you look at other possible characters with an Egyptian origin that she could be?

Honestly, I didn’t come up with the name. I didn’t connect her to the Scarlet Scarab. Sometimes Marvel picks a name and then gives it to the character that is developed [for the show]. Like, Arthur Harrow is absolutely different than the Arthur Harrow that is in the comic books. We’re just using the property. So we’re creating Layla free of all of that and then we gave her a name. I keep saying she might not be the Scarlet Scarab. Because right now, she didn’t get her powers through the scarab. But maybe, if the story continues, that’s gonna happen — or not. So the name to me is not important. What she represents is what’s more important. I can’t wait to know one day, is she still going to be a temporary avatar? Is she going to accept it? What is going to happen with her? I don’t know.

It sounds like you do, but I’ll ask directly: Would you want to work with Marvel Studios again?

I would pay to do that. Definitely. I wanted to be a director because I have stories that I want to share with as many people as possible. I’ve always made intimate films. My dream is to do what Denis Villeneuve is doing — making your small, intimate films on a bigger scale, so you connect to more people. Thank God I had the chance to do that on this show. I still feel it has the DNA of my films, the small intimate films. I had allies like Oscar, Ethan, May and Marvel, backing me up to do that.

There are only a couple very glancing references to the MCU on “Moon Knight,” but there are no crossovers at all — up to the post-credits scene, where crossovers almost always happen. How do you feel about what that means about the show’s place in the MCU?

We had the freedom to place it whenever. I want to tell you the very first scene, there was a crossover, and the very end scene, there was a crossover. But as the story developed and we kept changing the scripts, we felt like, “We don’t need that.” All of us. It was a collective decision. And then I kept thinking: It’s a rule. There has to be a scene at the end that connects us to the MCU. But I think they decided, “You know what, the surprise is that there isn’t, and what’s going to make this show unique is it doesn’t need anything else.” The best compliment we get on the show is when people tell us, “This doesn’t feel like a Marvel show. It feels like a standalone show that feels more dramatic, more dark, grounded.” I feel like we succeeded in bringing Marvel more to our corner. So, so proud and happy.

This interview has been edited and condensed.