Robert Redford in 'Captain America: The Winter Soldier'
Robert Redford in 'Captain America: The Winter Soldier'

The big coup of "Winter Soldier," of course, was snagging Robert Redford to play Alexander Pierce, the ruthless senior SHIELD official and member of the World Security Council. It's a far cry from "All the President's Men" or "Three Days of the Condor," which was very appealing to the Cleveland-based Russos. They even took inspiration from Henry Fonda's iconoclastic turn in "Once Upon a Time in the West."

"The second his name came up we couldn't get him out of our minds," Anthony muses. "He's ridiculously perfect casting for the role. Then of course anxiety set in but Redford expressed interest in Marvel. He invited us to his office and made us lunch (quinoa salad with salmon). 'I have to be honest with you,' he said. 'I don't know what these movies are but my grand kids do.'"

Redford was easy to direct -- he showed up and nailed the performance. It was also a nice touch having Pierce ask Sam Jackson's Nick Fury if Iron Man could make an appearance at his grand kid's birthday party (but no flyover, he has to stay and mingle).

But then it's the little character details from screenwriters Christopher Markus and Stephen McFeeley that make "Winter Soldier" so delicious, such as Fury's casual reminiscence about his feisty grandfather during an elevator ride with Cap.

Captain America Winter Soldier

The most important relationship was the odd couple pairing of Cap and Scarlett Johansson's Black Widow, once again having fun with incongruity: "It's irresistible, the mix of opposites," Anthony suggests. "She's somebody who deals in lies, the truth is very fluid, and Cap deals in the truth and has a very simple, straightforward code, so to put them in pressure situations together and to force them to either rely on each other or not was a big part of the fun and storytelling challenge for us."

Meanwhile, collaborating with Industrial Light & Magic (under the supervision of Russell Earl) provided an invaluable lesson in VFX while allowing them to indulge in hero worship. "Growing up on 'Star Wars' films, I went to the theater at 11:00 am to see 'Empire Strikes Back' and stayed until 11:00 pm after watching it four or five times in a row," Joe recalls. "They're still good at what they do, and we had a strong mandate that we wanted the visual effects to look as realistic as possible. And I thought they did a tremendous job with that third act [an intense battle featuring the next-gen, fully weaponized Helicarrier], which is a massive visual spectacle. 

"It was a challenge to the filmmakers shooting in a more hand-held verite style, which is not common for strong visual effects movies like these, so that was something that they were very sensitive about studying and trying to replicate that spirit and that texture in the visual effects."

It all comes down to deconstructing the mythology. "We always like edge -- anything that's mature," Joe adds. "That's why I liked 'Empire Strikes Back' as a kid. It was the most mature of those three films and treated me the least like a kid and the stakes were so high and it was so emotionally impacting. You want to please the 12-year-old in yourself but you also want to please the 40-year-old in yourself."

"At the end of the day, this movie was always a two-hander," Anthony adds. "The relationship between Cap and Winter Soldier is not resolved, the story is not over, so we're very excited about going back to work with Marvel on 'Cap 3.'" 

But the brothers want to first gauge audience reaction to "Winter Soldier" before diving head first into developing a sequel that will apparently go head-to-head on May 6, 2016 with rival DC's "Batman vs. Superman."