“Endgame” shares some unexpected parallels with “Game of Thrones,” which also recently ran episodes about its heroes preparing for a significant battle and then the battle itself. Why do you think these narratives are similar? Did you ever look at “Game of Thrones” for inspiration?

MARKUS We’re in a high-stakes time and a jarring time in history, where you have to contemplate what you’re willing to do to improve the situation. Whether or not everyone’s speaking to that, or just good old-fashioned storytelling, I don’t know.

McFEELY Marvel has been accused of being the most expensive television show there is, and there’s some truth to that. The genres are different, the tones are different, but it’s serialized storytelling.

MARKUS We occasionally wonder, did we just make the world’s most expensive inside-baseball fan service? But then we go, the fans are actually the majority of people who come to this. It’s inside baseball, but everyone is following the baseball. That’s also why the Marvel characters have lasted this long. They’re weird. They have strange quirks.

McFEELY The bland ones don’t last.

MARKUS I remember “Game of Thrones” being a reference for the first movie. How far apart can you keep these strands, and for how long, and still feel like you’re telling a single narrative? “Game of Thrones” has people who are just meeting now! As much as people think the culture’s going down the drain, there seems to be an elevating of people’s estimating of the kind of narrative that will succeed in popular culture.

McFEELY Whatever you think of this movie, it’s complicated. It is not another sequel.

MARKUS And a lot of popular TV is complicated. “This Is Us” is complicated. “Simon & Simon” was not that complicated. Great as it was. But it does seem like there is an acceptance of more complicated forms of storytelling.

Was the three-hour running time of “Endgame” ever in question?

MARKUS There was an agreement within the whole group that we’re going to take our time; we’re not going to cut a half-hour of it so we can get one more screening in per day.

McFEELY We couldn’t! Where are you going to cut a half-hour? There was not a sequence you could cut.

MARKUS Look at some of the most popular movies of all time. They’re long as hell. When people want to see something, it doesn’t seem to get in their way. There’s some short, totally unsuccessful movies, too.

Journey’s End

Why does Natasha Romanoff have to die?

McFEELY Her journey, in our minds, had come to an end if she could get the Avengers back. She comes from such an abusive, terrible, mind-control background, so when she gets to Vormir and she has a chance to get the family back, that’s a thing she would trade for. The toughest thing for us was we were always worried that people weren’t going to have time to be sad enough. The stakes are still out there and they haven’t solved the problem. But we lost a big character — a female character — how do we honor it? We have this male lens and it’s a lot of guys being sad that a woman died.

MARKUS Tony gets a funeral. Natasha doesn’t. That’s partly because Tony’s this massive public figure and she’s been a cipher the whole time. It wasn’t necessarily honest to the character to give her a funeral. The biggest question about it is what Thor raises there on the dock. “We have the Infinity Stones. Why don’t we just bring her back?”

McFEELY But that’s the everlasting exchange. You bring her back, you lose the stone.

Was there a possible outcome where Clint Barton sacrifices himself instead of her?

McFEELY There was, for sure. Jen Underdahl, our visual effects producer, read an outline or draft where Hawkeye goes over. And she goes, “Don’t you take this away from her.” I actually get emotional thinking about it.

MARKUS And it was true, it was him taking the hit for her. It was melodramatic to have him die and not get his family back. And it is only right and proper that she’s done.