The "Age of Ultron" has yet to arrive in the Marvel Cinematic Universe, but two of the upcoming "Avengers" movie's biggest players are already preparing themselves for war -- "Civil War."

During a press junket promoting the May 2 release of the anticipated sequel, Robert Downey Jr. and Chris Evans, or Iron Man and Captain America, if you prefer, jumped ahead a little and broke down what will cause the break down between their characters in the next "Captain America" sequel.

"[Tony] Stark grew up under the shadow of this very close father son/relationship that Howard [Stark] had with Steve [Rogers, Captain America] so I'm sure that it's driven by some unconscious motives," Downey told IGN, cutting to the core difference between the heroes. "At the same time, they're two vastly different generations of moral psychology. And arguably, Cap's is more righteous. But I think Tony is a realist. So that's always a fun dynamic to play."

RELATED: New "Age Of Ultron" Featurette Explores Avengers' Team Dynamics

"[T]here's a flip-flop in the way we approach things," Evans added of the "Civil War" set-up. "Tony's always been a trailblazer. He's always been his own man and he bucks authority. He dances to the beat of his own drum. Cap comes from a world or order, and organization, and hierarchy, and structure. And I think after 'Cap 2' when S.H.I.E.L.D. kind of fell that Cap kind of realized that you can't necessarily trust the people around you -- or you can't trust the system. I think he now is kind of starting to follow his own heart, and do his own thing, and as a result there becomes this kind of flip-flop in perspective."

Opening May 1, "Avengers: Age of Ultron" stars Robert Downey Jr., Chris Hemsworth, Mark Ruffalo, Chris Evans, Scarlett Johansson, Jeremy Renner, Don Cheadle, Aaron Taylor-Johnson, Elizabeth Olsen, Paul Bettany, Cobie Smulders, Anthony Mackie, James Spader and Samuel L. Jackson.