It’s time to talk “Avengers: Endgame” spoilers.

Sure, the epic Marvel movie may have raked in a record-breaking $2 billion at the box office, but what about the decisions made in the film that will forever affect the status of the Marvel Cinematic Universe? What standout moments made fans cheer, and what was just fan service?

Variety talked to the writing duo that has spent over a decade trying to close out this chapter of the MCU, Stephen McFeely and Christopher Markus, and pressed them on all the burning questions raised in “Endgame.”

WARNING: If you still haven’t seen “Avengers: Endgame,” proceed no further. This conversation is full of Marvel spoilers.

This isn’t the first Marvel movie you guys have worked on. Was “Avengers: Endgame” the one you had the most trepidation about tackling? Tell me about the journey to get to “Endgame.”

Stephen McFeely: We were nervous at that moment because it was such a big project. It would take up so much of our lives and it would be the biggest puzzle that we ever would put together as writers. That was scary and we we said okay, we should probably do scary things and if successful, it might be really amazing.

Christopher Markus: We knew this would never come around again. For someone to offer you the culmination of this big of an undertaking, that’s never going to happen again. And as consuming and sometimes painful as it was over the past four and a half years that we’ve been working on it, it will never happen again. To walk away from it would seem like something that you’re really going to kick yourself about later.

When did you decide what character was going to die before “Infinity War”? How much of that decision stemmed from, “This is the story we want to tell” versus, “Yeah… Robert [Downey Jr.] is done.”

McFeely: Both films were conceived and outlined together. We didn’t start writing “Infinity War” until we knew what the end of “Endgame” was and that is a conversation that’s happening mostly with Kevin [Feige], Trinh Tran, Anthony and Joe Russo and us. In general, it’s how do we play off characters? And I don’t know if finances or actors really had that much to do with it. What we were trying to do was lead with what’s best for the characters. We felt that that meant that some characters might come to an end because they make an ultimate sacrifice and that’s the end of the journey for them.

Markus: I think part of the reason people are finding this so emotionally satisfying is these were characters who had been on paths for over the course of the 22-movie saga and those paths demanded an end. It’s not a situation where you can roll out a James Bond movie every two years, where you just wanted him to keep going ’cause that’s what he does.

These people started out in a certain place that had problems that needed fixing and arched over to a point of completion. So, it really is the rightful and fitting end for them. I think if we kept Tony alive or if we killed Cap, it would have rung false.

Let’s break down some of the bigger scenes. The first standout is all the Marvel women running across the battlefield together: “She’s got help.” Where did this idea generate from from and who came up with it?

Markus: We’ve been on this for so long, it’s pretty hard to attribute any specific ideas to any one person at this point. We had such an embarrassment of riches in that whole sequence. How do you make it not just a blur of people all the time? So, we found ways to sort of separate off certain units so you could focus. And Marvel fans, increasingly, with every movie, [have] gotten these great female characters. Some people can call it pandering but it’s also like we have tons of shots of all men. Why not have a shot of all women and they’re so cool? It just seemed like “Let’s celebrate it!”

McFeely: I remember on the day we shot that, every woman on the crew and in the offices came down and were sort of milling about behind the cameras. That was, perhaps, the most moving part of it for me, how important it was for everybody to see it.

How were they reacting?

McFeely: They were pumped. There was a lot of pumped circumstances around it. I agree with Chris. We certainly thought long and hard about whether it had been earned. We really wanted most of these moments to be earned and not just a delightful piece of fan candy. Honestly, it made me nervous and sometimes, we would bring it up: “Do we keep it? Do we not keep it?”

And pretty much we all said, even me, “God. I’d rather see it. I’d rather it be in there and make a big conversation and some people won’t think we earned it.” Everyone wanted to leave it in the movie.

Fans have been asking for an all-women MCU movie ever since pictures dropped online of all the actresses together. However, critically, some people do seem split on that moment in “Endgame.” When you give fans what they want, what risk do you run with being called fan service or pandering? And that being said, some critics argue that this fan service is good.

Markus: Oh, sure. These movies would be nonexistent without the fans. So, you know, a movie that is made to frustrate fans seems a little suicidal.

People say “fan service” like you are pandering to some niche. I mean, we’ve all seen the numbers that these movies make. The fans are the majority at this point. Fan service is simply honoring the stories that have come before. It’s not like we’re pulling out a tiny Easter egg that only three people are going to get. It’s just tying up the threads; it’s picking up the nuances that have been dropped earlier. I don’t see it as any kind of niche writing.

Now that the fans have had a taste of an all-women Marvel moment, do you think the studio would ever make a MCU feature film based entirely on a group of women?

McFeely: Listen. We no longer work at Marvel….

Markus: God knows what they’re planning.

McFeely: Certainly representation is super important for them going forward, and has been for a while. So… maybe? That’s a big fat maybe.

Let’s talk about the “Hail Hydra” scene. In addition to the all-women moment, fans really went nuts over Captain America recreating the elevator scene from “The Winter Soldier.” When did you know you were going to revisit this?

Markus: In plundering our past to figure out the time travel fractions, at one point, we had thought about going back to the Triskelion, which is the big building in “Winter Soldier,” because the Mind Stone had been there. That’s when the concept was born. When we switched over to Stark Tower, everybody loved it too much to leave it there. So we moved it over. But you don’t want to just do the same scene again. I mean, that was the challenge for the whole second act: how do we revisit the “greatest hits” but put a new spin on them each time so it’s not just a clip show? We couldn’t go back in the elevator and have another fight, so how do you get out of the fight?

On the passing of the shield, there were two people that Cap could give his shield to: Falcon (Sam Wilson) and Winter Soldier (Bucky Barnes), and both of those people were standing in the same scene.

Markus: Both of them have picked up [the shield] in the comics; Bucky and Sam. But, when you look back at “The First Avenger” and realize why he was chosen to be the first super soldier, it’s about a certain purity at heart and a certain inner heroism. It’s pretty hard to give it to Bucky. As much as we love him, he is on the dark path and is recovering from that. Sam really is a truly stand up guy. It wasn’t a wildly difficult choice, certainly. I think Bucky has a lot more story as Bucky and as someone headed on a path of atonement. And Sam has ascended into this new role.

McFeely: Right. That’s the thing that gets me the most is that it’s much better for both of their stories this way. Certainly Bucky getting the shield would provide lots of story. I don’t know if it gives Sam much story. And again, there’s a streaming show coming, right? And I don’t know what they’re doing but Sam having the mantle of Captain America, how he feels about that, and Bucky working or having some kind of relationship with Hydra, I think that’s pretty rich. Again, particularly as Bucky has to confront the mind control past. Captain America has always represented the best of the idea of America, you know? And giving it to an African-American guy… it’s great. Not patting ourselves on the back, I’m just saying that’s pointing toward a better America.

Undoubtedly again, I don’t know what they’re going to do with that [in the streaming series], but how does Sam feel about it? Sam is his own superhero. He’s got his own identity. What does it mean to be saddled with another guy’s identity? Do you embrace it? Do you push it away? There’s a lot of good metaphors that you could work with.

Markus: Exactly. What is he taking on by becoming “the symbol of country”? It’s what keeps the idea of Captain America fresh, right?

Let’s keep going. Let’s write this Disney Plus series right now! Quick question: did you actually write in the script, “Bucky nods in agreement,” implying that he’s cool with the passing?

McFeely: Yes. Yep.

McFeely: Our assumption is that he and Steve had long conversation before Steve went back.

Captain America has been a huge, huge part of your lives for a long time. Why is it time for Steve Rogers to retire the shield?

Markus: Steve Rogers has … boy, he has done all you can do. He’s well over 100 … I think he’s over 100 years old. He has fought World War II and Civil War and an Infinity War. He’s been through three wars. And he has come to a place, I think, where he’s realizing to be a fully rounded human, which is all of our goals, he needs to take a little time and be a little healthier. I think when he … in a way I think when he encounters his old self back in Avengers Tower, there is a processing going on in his head that well, that’s a really intense and maybe not 100% healthy guy. So I think it is time.

McFeely: We figured out pretty early that … and we’ve been helping do this for a few years now, that Tony and Steve were sort of on crisscrossing arcs. That Tony movie by movie was becoming … was having a more a macro view, becoming more selfless. And Steve was becoming a bit more self interested. Civil War is a good example of that. So, we had put up on the wall at one point, Tony becomes a complete person when he loses his life and Steve becomes a complete person when he gets one. We drove toward that.

Now more specific questions: Who is the kid at the funeral?

Markus: That is Harley, the boy that Tony Stark bonds with and helps out and leaves a legacy to at the end of “Iron Man 3.” He’s grown quite a bit.

Why was actress Katherine Langford cut from “Avengers: Endgame”?

Markus: Ah … It was … that just … it didn’t work in the final cut because it was just killing the momentum of the rest of the movie.

McFeely: And she was great.

Markus: Yeah. She was great. It was just a very sort of ruminative scene in a time when you really wanted to be on the plot. And as much as … and it also, because of its nature that we’re going through, we couldn’t move. It’s not a scene you could say, “let’s try it at the beginning.” It only made narrative sense where it was, but it didn’t make pacing sense. So it just had to go.

Of all the TV characters to integrate into the MCU, you choose Jarvis from “Agent Carter.” Why him?

McFeely: Well, for a very small section of the audience who watched “Agent Carter,” it didn’t require a big leap. And if you caught who he was, great. If you didn’t, great. It’s a little different from putting the Defenders in the final battle. That’s a lot of people that you’re going to scratch your heads if you don’t subscribe to Netflix.

Markus: And there’s also some wonderful continuity for his character in that he was Peggy Carter’s right hand man. He was Howard’s butler. Tony’s mentor, respectively. Tony named the AI that later became Vision after him. More than any of the other TV characters, he really fit in the continuum and he would’ve been there in that moment. It’s not like we had to bend over backwards.

How long did you know that Iron Man’s last words were going to be the very famous, “I am Iron Man”?

McFeely: Oh, late. We did not figure it out until late. In fact, that’s a re-shoot. We tried a bunch of things, they weren’t quite as satisfying. And we sort of … actually, I don’t know if we had Thanos say what he said, but it became a rhythm thing. When he says, “I am inevitable,” he kind of has to deny him something. Sometimes we try to avoid the low-hanging fruit. It seemed very obvious and we resisted it. But it felt all kinds of perfect. So we came back to it.

What was the best ad lib line on set? Was there an actual ad lib moment in this movie?

Markus: Oh sure.

McFeely: But then when we tell you them, you’ll be slightly less impressed with us.

Markus: I will say, I think this was an ad lib because I don’t remember it. I loved every time when Scott Lang [Paul Rudd] runs to his old house and finds his [previously] 5-year-old daughter Cassie. After their big emotional hug, he pulls her away and goes, “You’re so big.” Which I don’t think we wrote. It’s what you say to children when you haven’t seen them in a while. But it takes on this big, bizarre meaning when you look at context, [it] made me very happy.

How is it possible for Gamora to come back, but not Black Widow? Since they were both killed by the Soul Stone.

Markus: It’s not the Gamora that was killed by the Soul Stone, that is the Gamora from the past. When Gamora went off that cliff, the Gamora from that time period died. But this is the Gamora from prior to that. So she’s still alive, she traveled in the time machine to the present. You know, like you do.

McFeely: As you do.

If they took Black Widow from a different timeline, you’re saying it would’ve affected her future, possibly? Or she wouldn’t have been able to sacrifice herself for this?

Markus: Well, it would’ve been a weirdly selfish decision. Like, effectively, we’re going to kidnap a version of Black Widow who knows nothing about the current circumstances and bring her to the future just so we can have one. It’s not really asking her whether she wants to go.

Also, does this mean that Thor is without Mjolnir for most of “Thor 2″?

Markus: I guess technically, although Steve would go back and erase that timeline by returning the stone to the moment it was taken. How he does that requires getting it back in Natalie Portman. I don’t know, but the idea is that the timeline would be erased, according to the Ancient One.

Related: