After delivering the highest-grossing movie of all time (NBD), nobody would've blamed Joe and Anthony Russo for shutting it down for the rest of the year and taking an extended vacation/victory lap. Instead, they're currently in Toronto promoting the first film produced by their newly formed studio AGBO, Mosul.

Shot entirely in Arabic, the film's an intense war movie about the Ninevah SWAT team, an elite Iraqi police force locked in a desperate fight against ISIS in the war-torn city, and features a cast of relative unknowns, a far cry from the A-list ensemble the Russo brothers assembled for Avengers: Endgame. It's also based on a true story, adapted from a 2017 New Yorker article called, fittingly enough, "The Avengers of Mosul."

There's a more concrete Avengers connection here too: The article was first brought to the Russos' attention by Endgame (and Avengers: Infinity War and Captain America: Civil War and Captain America: The Winter Soldier) screenwriter Stephen McFeely, who's a partner in AGBO along with his co-writer Christopher Markus.

"While we were all still executing Infinity War and Endgame, we would talk a lot about it on set — thinking about what should be our first project," Anthony Russo explained to SYFY WIRE when we sat down with the brothers, as well as Mosul's Iraqi executive producer Mohamed Al-Daradji, at TIFF. "Steve brought us this article and said, 'This is the most amazing article I've ever read,' and we agreed with him. It moved us really profoundly."

And even though they were in the middle of the massive years-long production that was Endgame, they didn't want to wait to get started. "We felt a real sense of urgency that not only does this story need to be told, but it needs to be told ASAP," Anthony reasoned. "Because the conflict was still going on." (And is still going on to this day.)

That meant cashing in on their Marvel cred immediately in order to get Mosul off the ground.

"There's no other film company that would've made this film," Anthony argued. "From the very beginning, it was a challenge to Joe and I to do everything that we could to try to shepherd this movie through the system properly, because I don't know that anybody else ever would've."

It also meant deciding to shoot the film in Arabic, part of an effort to make the film as authentic as possible, to tell this story from an Iraqi point of view. Enter Al-Daradji. "I came on board when I read the script that Matthew [Michael Carnahan] wrote. It was actually one month after the liberation of Mosul, and it was very emotional to read. Because I was just there a couple months earlier," Al-Daradji said. "It was very important to me to be a part of this process and to work with the whole team."

"Look at photos of Mosul: The level of destruction is staggering. Staggering and almost incomprehensible," Joe Russo said. "So the intent here was to bring audiences into that world in a way that allowed them a window into the pain and the suffering, and the fight for human dignity that was happening in that city."

Credit: Conde Nast Entertainment

To some, it may seem like a bit of a left turn to go from superheroes to Iraqi soldiers, but the Russos don't see it that way. "We've had a really varied career. A lot of people are heavily skewed toward our Marvel work, but we started as very low-budget, independent filmmakers," Anthony explained, saying the brothers also grew up with a keen interest in politics and international affairs. "We tried to imbue our Marvel work with a strong international sensibility, and a lot of world politics and world issues. So for us, it feels like a natural extension."

"We love that level of filmmaking that Marvel afforded us. We love telling stories on that level, but we're also fed by smaller stories and more specific stories," he continued. "So for us moving forward, it's moving back and forth between the two."

Which is why, even though Endgame closed the Russos' Marvel chapter for now, that door isn't shut for good.

Asked what it might take to bring the brothers back to the MCU, it sounds like the recent Fox merger offers plenty of enticing possibilities. "I grew on up [John] Byrne's X-Men run. Ben Grimm was a favorite character growing up, the Thing. And Fantastic Four is now in the Marvel fold. There's a lot," Joe said. "Silver Surfer is an amazing character. Going really big in cosmic would be a lot of fun. So there's a lot of things that could attract us."

And if/when they do come back, they're far more likely to jump in with both feet into another multi-movie arc, as opposed to just popping in to helm an episode or two of something for one of the many Disney+ Marvel series recently announced at D23, he said.

"I think after you go on the journey that we went on –—because there is a comprehensive narrative, an overarching story from Winter Soldier all the way to the end of Endgame that involves Tony and Cap, through Civil War, through Infinity War — I think that scale of ambition in storytelling is a bug that's bit us," he said. "And we're compelled to tell more stories on that scale, with that sort of years-long ambition to them."

"I mean, look, working with Kevin [Feige] and Louis D'Esposito and Victoria Alonzo has been the most rewarding collaboration we've had in our entire career. They're like family to us now. We're all very, very close to one another, and we miss each other," Joe continued with a laugh. "So I'm sure we'll find something that we can do together soon."

Paging Dr. Richards ...