There is so much riding on superhero movies these days that it can sometimes feel like a torturous task. It’s certainly how Joss Whedon felt after making Avengers: Age of Ultron.

“It’s weird because the first one [Avengers: Assemble] was very, very, very, hard,” the director said after Ultron’s release. “This one was much harder. It a little bit broke me.”

The Russo Brothers were confronted with an even more ambitious task by making the next two Avengers movies back-to-back but explained to Yahoo Movies why it didn’t break them.

“I think because there are two of us it was a very different experience for us,” Joe Russo said. “It’s a lot; he’s writing, he’s directing, he’s doing it all, he’s going home at night and reworking the script, but there’s two of us and it would be hard enough to try to accomplish one of these movies in a year. We did two of them.

The Russo Brothers talk Avengers: Infinity War More

“Because we had done two prior Marvel films, we had a system in place, we work with the same crew, we have a great support system. We have an incredible VFX team that’s been working with us on all four movies, our DP has been with us for all four films, so we developed a shorthand where we think we can move efficiently now through the material.”

There was certainly a lot of material; Avengers: Infinity War boasts the most Marvel heroes ever, an “unprecedented” amount Anthony Russo explained.

“I think we are just struck with the amount of people we were able to work with which I think was an unprecedented number of characters in a single film,” he said. “I don’t think anyone has seen a movie like this before and I think we’re just grateful for the opportunity to bring the people to the table who we were able.”

In the past, Joss Whedon has said he was unable to work with Thanos as the main villain because he didn’t know how to make him relatable. The Russos found that it’s because so little was done with the character that they were able to weave a narrative around him.

The directors treated Thanos like a hero by making him just as complex More

“Well, that was our whole jumping off point with the story because we knew that the characters had been so lightly teased, so far, that I think we began our whole process in thinking about these movies like, who is Thanos really?” Anthony said.

“Realising that he was the touchstone that would connect every single element of the MCU led us to start thinking about him as the central character of this movie and so we filled him out in a very complex level.

“He’s one of our favourite characters that we’ve worked with so far in the MCU and Josh Brolin is such an amazing actor, he brought an amazing performance and an amazing complexity to it,” the co-director continued, “but he’s a very complex character. In the same we like our heroes to be complex we like our villains to be complex.

“There is a dimension to him that is altruistic, he has an intelligence and he actually believes that what he’s doing is going to be good for people, even though his means of achieving it are sociopathic.”