How the MCU worked Captain Marvel into the Avengers for Endgame

For all the jokes Marvel's actors and creatives tell about the horrible things that could happen if they spill vital state secrets, the future of the Marvel Cinematic Universe is very much under lock and key. Mark Ruffalo (Bruce Banner/The Hulk) and Tom Holland (Peter Parker/Spider-Man) might be beloved for fumbling their way through spoilers — Holland got so loose that he didn't even get a script for the upcoming Avengers: Endgame — but for the directors, producers, and general corporate mechanisms behind the MCU, these secrets are the franchise's lifeblood.

When SYFY WIRE spoke with Avengers: Endgame executive producer Trinh Tran after the film's international press conference in Los Angeles over the weekend, she confirmed just how important these secrets are to the MCU's future.

During the press conference, long-time Captain America actor Chris Evans seemed to come closest to spilling the beans. When asked about his character's journey from 2011's Captain America: The First Avenger to Endgame, he seemed to hint at Endgame being a true endgame — at least for Steve Rogers. Halfway through a "broad strokes" explanation of "the completion of the arc," Endgame co-director Joe Russo half-jokingly made a buzzer noise to cut Evans off. Everyone laughed, and Evans stumbled over a couple more attempts at answering the question before giving up.

Karen Gillan (Nebula) joked about becoming incredibly nervous while answering a question, Paul Rudd (Scott Lang/Ant-Man) started off with "I'm terrified to say anything," and Clint Barton actor Jeremy Renner was practically nonexistent in the room due to his inability to speak about his MCU return. All of this is to say that while the MCU has always been secretive, Endgame is on another level.

And so we turn to Tran, who's been keyed into the MCU since the beginning, working her way through the ranks from being an assistant on 2008's Iron Man to a creative executive on 2014's Captain America: The Winter Soldier.

As an executive producer on both last year's Avengers: Infinity War and the upcoming Endgame, Tran is privy to an Infinity Gauntlet's-worth of information. This includes the cast's reaction to the final scene filmed for Endgame, Captain Marvel's entry to the Avengers, how those upcoming Disney+ shows might change the MCU, and, most importantly, whether or not the MCU will ever show anything more explicit beyond a brief kiss or flirtation.

Read on for SYFY WIRE's full interview with Tran. Avengers: Endgame premieres in theaters on April 26.

What was the reaction on set on the very last day of filming Avengers: Endgame?

Well, we filmed both Infinity War and Endgame back to back. So it was like a whole long year of shooting. I think one of the longest [shoots] or Marvel has experienced. It's been four years of this experience with the Russo brothers, and 10 years with some of these cast members. So the feeling is it's a little bit bittersweet in that sense. You know, we've all grown to just love each other and it's become like a family dynamic in that sense.

For every movie, after you're [finished] shooting it, you kinda just don't want it to end because you've grown so attached to these few people that you've worked with for so long. So there was that feeling of, oh, we don't want it to end, but it's actually exciting because we want to get this going in post-production and get it out to the world to have everybody see it.

You've said there's a specific reason why the characters who survived through Infinity War did. Does every single one of the characters who survived the snap have a specific skill set that no one else has that will help them through Endgame?

Oh, that's a great question. Skill sets, huh? I think with all of these characters, there's a character arc in each one of them that they've developed a particular skill set that will always be helpful in each and every one of those movies, right? So with the survivors, they're going to bring forward what they have learned and what they have evolved as characters in their different franchises, which will carry on to this particular movie, which, uh, I can't say much about. [Laughs].

For example, Cap is a leader. He's always going to be that. He's always going to be striving to be the best and righteous person that he is. And you know, you can't lose sight of that because this is the character from Captain America: The First Avenger that you've seen go from — we call him skinny Steve — to a hero who everybody idolizes and who everybody looks up to. So you want to be able to take that and take that character that we've developed for the last 10 years and bring those particular skill sets into this big movie.

We talk about Captain America being a leader. So is Captain Marvel. There's been chatter online, as there always is, about how crazy-powerful she is — like Thor, but fully realized from the beginning. Given all that power, what was it like integrating her into the team in Endgame?

I think it never hurts to have a strong female to come into a group, the majority of them men besides Scarlett [Johansson's Black Widow], a super strong female hero.

But one of the very few for a long time.

But one of the very few. So to have such a strong character come into play right from the beginning, I think it's very helpful to the team. [Laughs] They need all the help that they can get. So I think it's nice to see somebody not go from the usual — they start off weak in that sense and then they sort of build into this powerhouse, but to come in just as strong as they all are. They're going to look at her and go, "Hey, who is this person?" So I kind of liked the fact that there is a female that goes straight into it that way.

Looking down the line, is there an endgame, for lack of a better term, for Phase 6, Phase 7? How far out are you looking?

We have a lot of characters at Marvel that haven't even touched the surface. So there's a lot to explore. We're always talking about what the future can be. I can't get much into detail about it, but there is a lot to explore.

But what I can say, what I am happy to say, is that we're always striving to look for more diversity. With Black Panther, with Captain Marvel coming out, [it] opens a lot of doors for that and allows us to see that audiences really are embracing these types of characters, this sort of diversity that people are just really connected to. So to be able to see that allows us to just go, "You know what? It's okay to think about more stuff like that." So I'm excited for that.

Credit: Marvel Studios

Is it one-off movies from here on out for a little while?

[Laughs] You're gonna find out!

How married is the Marvel Studios team to a greater plan? Is there some room to put aside a plan that might already be in place to bring in something greater?

I have to say, 10 years ago, if you asked if we would be here right now...

Never in a million years.

Right? Who knows, right? Who knows. So we're very happy that we are where we are right now. But I always say Kevin Feige, a genius. He saw a world that we were able to put these franchises in, interconnect them and the characters in a way that no other company has done. He saw a vision and he had a general idea of what he wanted and he brought that to life, which is amazing.

So look, in the future, there's always the plan, but there's always wiggle room to do anything, right? Because we're going to see how the audience is going to respond to certain movies and that's actually going to help us determine whether we want to go in a slightly different direction that will allow for people to embrace the movies, the future movies, and the future of Marvel a little bit more. So there's never really a strict, particular direction we're going to go towards per se. It's really just embracing what people want to see.

Is there any particular reaction from moviegoers in the past that changed the course of the MCU?

Oh. You know, I can't recall off the top of my head. I think in general, people have just been very excited with each of the franchises that have come out and how they've connected into our previous movies leading up to here. So I can't recall at the moment if there was anything that kind of set it in a different course. I have to think about that a little bit more.

Credit: Marvel Studios

Last question. A very stupid question, but an important one. Will there ever be an MCU sex scene?

Oh! [Laughs] Part of Disney? I'm not so sure about that. [Laughs] I don't think so.