With three billion dollar Marvel films under their belt, including this year’s Endgame sensation, Christopher Markus and Stephen McFeely have moved on to their own production company with the Russo brothers. But the Marvel family never strays too far, and the superstar screenwriters shared some of their post-Phase 4 possibilities with Screen Rant.

Endgame has such a huge cast. Was there anyone that you wish you had to chance to play with a little bit more?

Stephen McFeely: Anybody who comes back, who was snapped obviously, gets this much room in the third act. We designed it so that it's mostly just action. We tried to carve out beats where people sort of hug and ask, “Where you been?” and “What's going on?” and “What the hell?” But those just went by the wayside, because we’ve got stuff to do.

Christopher Markus: Yeah, and it's hard to say. Certainly, there would have been people who were fun to explore. But the movie did not need it.

Stephen McFeely: I will say, there was a moment I really liked. I thought we really needed it, but we never shot it. It was Winter Soldier saving Tony or Pepper on the battlefield, and then having a moment with Tony where he’s sort of forgiven. Or at least acknowledge that that that guy's not a murderer still. I mean, he's murdering aliens, but…

Did Tony forgive Bucky? I don't know.

There’s also a moment when all the heroes take a knee. Why did that get taken out? It's such a beautiful scene.

Stephen McFeely: Momentum; it’s momentum.

Christopher Markus: It was a bit doubling the funeral. We're having a long somber moment, and now we're going to milk it.

Stephen McFeely: We'll just be dressed up and have the same moment.

Why did you decide to do time travel rules so similar to the comics?

Christopher Markus: They travel through time constantly. I recall Cap getting shot with a time bullet?

Stephen McFeely: It was practical. If you do Back to the Future rules – which everyone sort of assumes is how time works, it’s a great movie because everyone goes, “Well, that's how time travel works.”

So, we had physicists come in and they said, “We don’t think it probably works that way. It's more like branch realities.” If you die, you die. You can't go kill your grandfather, because you're still here.

That helped us, because if we were to go back and step on a butterfly every time we got another stone, then it would just be crazy over here. It's just an exponential branch off a branch off a branch.

Christopher Markus: It would also mean you solve the problem very quickly.

Stephen McFeely: You would just had to do one thing.

How do you celebrate Endgame becoming the biggest movie of all time? 

Christopher Markus: I will tell you what I did the other day. I mean, I didn't do it. Marvel has had made for all the movies little one-off posters drawn by comic book artists. And I had them all framed finally. They've just been sort of stacking up in a special box with me going, “One day. I’ll do something with them.”

I finally had them all framed, so the entire Marvel collection – I have three Caps, two Endgames, four The Dark Worlds and an Agent Carter. Biggest movie the world, I can blow some money on framing.

Robert Downey Jr. as Tony Stark aka. Iron Man in Avengers: Endgame

What do you do to celebrate, Stephen? 

Stephen McFeely: I didn't celebrate or anything. For Infinity War, when it broke the record, I remember going, “Holy crap” on a Sunday morning. “That's amazing.” I had no idea; I got emotional.

But then with Endgame, it was sort of assumed it would do something like that. And then it just blew the doors off, and I just walked around like, “I think everyone's at the movies this weekend, right? Crazy. The streets are empty.” It’s like the Super Bowl or the snap.

So, no, I didn't buy anything or throw a big party or anything.

Was there ever any chance that some of the TV characters, like the Agents of SHIELD or the Defenders, would have been involved in this at all?

Christopher Markus: At the very beginning, we were like, “That is possible.” But it came down to, frankly, just timing. The sequential timing of the TV versus the movies; I wouldn't even know where they are in their chronology to use them. And then for us to say that some of them blipped or didn't blip is just fucking with five writers’ rooms.

Stephen McFeely: We already were demanding so much from the audience. Like, if you want to enjoy this the best way it possibly can be enjoyed, you gotta watch 21 other movies. Oh, but wait, and several episodes of streaming services you need to pay money for.

Christopher Markus: The best we could do was to bring Jarvis back. Put Jarvis in a wig.

Sam Wilson becomes Captain America at the end of the film. Can he physically wield the shield without the super serum?

Christopher Markus: I think the shield, he can. Anyone can pick up the shield.

I'm gonna get deep in the dorky weeds here. Theoretically, if something absorbs vibration, this violates its own rules because it shouldn't hit you that hard. When he hits criminals with it, it should kind of woosh off. Like, I keep hitting you and nothing happens.

My question always is, does he keep the wings and the shield? It becomes very odd. Which is interesting. I have no idea what they're doing with Captain Falcon, but I've always wondered what it’s like?

Stephen McFeely: Design-wise?

Christopher Markus: Not only design-wise, but personal choice-wise. I developed this character myself. I'm the Falcon. I've got the wings. This is who I am. Now I'm being given somebody’s leftover costume and being told it's cooler than the one I have.

There’s a chance you can be insulted. Like, I don’t wanna change!

Stephen McFeely: I guess that's gonna come up.

Christopher Markus: They can do anything.

Stephen McFeely: I have high expectations for that show.

You introduced the Winter Soldier and the Falcon to the MCU. How do you feel about those characters being on the streaming service? Do you have the sense of a parent letting go of their child?

Stephen McFeely: Sure. I don’t know too much about the show, but it seems like it's in good hands.

Christopher Markus: I'm very glad they recognized how good those two are together. It’s a gold mine.

Stephen McFeely: We're in a new spot, so I can't even predict. How much screen time has Sam Wilson had in the MCU? An hour, maybe? We’ll get that in the first episode of this six- or eight-part thing.

Christopher Markus: I was about to say, we never even met any of his friends.

Captain America Falcon

What advice do you have for future filmmakers of the MCU?

Stephen McFeely: I certainly don't presume to give advice to people. But know you're playing in a comfortable sandbox, right? I think the audiences are ready to go almost anywhere you can take them, if you earn it.

Know that you've got Kevin and his team, who are really good and are excellent sounding boards. I would say don't be afraid to push things further. We got to Endgame because we were allowed to really break things open and destroy things. Don't be precious. Push it. I don't think you can break this. I think if you're honest and genuine about your intentions and the characters’ intentions, you can go to some really interesting places.

Christopher Markus: I would just say never write for the costume. Write for the character. That is a movie about Steve Rogers and Tony Stark and Natasha. If you start thinking, “I'll be so awesome if…” Those will come.

I think you mentioned that about Superman, as well. That your take on him would similar to Captain American, in that the person doesn't necessarily change but the time changes around him.

Christopher Markus: Yeah. There's alienation and there's weirdness to being a superhero and to thinking about those things. Not every movie needs to have an hour of sadness like ours did, but that's the only way you understand them and understand why they're doing stuff. We took a good long time with 90-pound Steve at the beginning of Captain America.

I could see other people going like, “That's the selling point. Let's start with it and maybe you can flashback every now and then.”

Steve Rogers, at least the way we know him, is no longer in the MCU. However, if Chris Evans said, “Hey, I want to come back,” do you guys have an idea how to bring him back?

Christopher Markus: In the present day?

Stephen McFeely: There's trouble at the old folks’ home. I don’t know.

I mean, there's certainly more stories to tell if you wanted to, given where he ended up. But no, I don't have a secret to get him standing next to Captain Marvel.

Christopher Markus: I also don’t want to. I love writing for Cap, I love Evans. But I really feel, much like Tony, we got them to a place where they don't need to do it anymore. I'd hate to gin up something hokey to get them back

Stephen McFeely: I do worry that if they do stuff like that, it'll ding Endgame in the rearview mirror. This is such an important and such an interesting moment in movies, because a very successful studio just put their tools down.

Last time we talked, you mentioned that you would be interested in doing Secret Wars if it was presented to you.

Stephen McFeely: I think Joe would make us.

Christopher Markus: As far as I remember, and I literally have not read that comic books since high school, it's…

There was a more recent one that came out, which had a pretty cool little story behind it.

Stephen McFeely: Listen, if Marvel calls, obviously we’ll take it very seriously.

Christopher Markus: I mean, my preference would be to go back to a single character and go small again.

Captain America Writers Christopher Markus and Stephen McFeely

Who would you have in mind? 

Christopher Markus: I don't have anybody in mind. There are people who I like the way they look, but I'm not entirely sure… For some reason, I think Machine Man looks awesome, but I’m not 100% sure what the story is there.

Stephen McFeely: I don’t even know his powers.

Challenge accepted.

Christopher Markus: I like Moon Knight, although he's got a show. It's probably better suited for a show because it’s complicated.

Speaking of the Disney+ shows, have you guys given any thought to doing one of these series for the MCU?

Stephen McFeely: We were thinking we'd go to TV because it just be a way to exercise more and have our hands on more things and run the show. So, we get to kind of do that on a small level here at AGBO films. But, yeah, we're open to TV. It's interesting.

Christopher Markus: And the streaming, it's a fascinating thing. Marvel used to make one shots, because they had dangling pieces of story. They don't anymore. Because you could literally make a show. You could do eight hours on Colson had Coulson not already had a show.

It's a weird Golden Age if you like deep dives. Like, you can get them.

Last question for the both of you. What is your dream lineup of Avengers? If you guys get to choose your own.

Stephen McFeely: Like we’re playing five on five basketball and I gotta pick a team.

There you go. Six on six.

Stephen McFeely: I need Strange, I need Captain Marvel, I need the Vision. I'm just taking power hitters, right?

Christopher Markus: I will say I would not choose Panther, because in the comics, there was always something in the order part of my mind that was like, “You can’t pause Wakanda.” Like, “Now I am on your super team for however long you need me.”

I think he's got to run Wakanda, but that's not to say Shuri in a suit couldn't come over.

Stephen McFeely: I'm adding Scarlet Witch to my lineup.

Christopher Markus: Yeah, I'm going to go the classic sidekick route. War Machine, Wasp, Shuri, Bucky and maybe… What would be fascinating, if they are in fact doing it, Jane Foster Thor.

More: Read Screen Rant's Avengers: Endgame Review

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