SAN DIEGO - Anthony Mackie is well aware of the Falcon's rather cringeworthy depiction in his early comic-book appearances - but he's happy with the way Marvel has turned things around.

"The one thing I appreciate about Marvel, is when they introduced this character, they realized the value of having an African-American superhero, and they continued to reintroduce him and put him in different contexts until they felt like they got it right," Mackie told me during an interview at San Diego Comic-Con to talk about his role in "Captain America: The Winter Soldier." "So he continued to evolve and change and be reintroduced, in a way that as we changed as a people, he changed as a character. And you know, you gotta appreciate that, you gotta admire that from people who realize...or admit what they had wrong. And in this movie [directors] the Russo brothers have really given me the opportunity to make him into a three-dimensional character instead of just a cookie-cutter out of what Marvel thought he was at any point in time."

Coming off of Michael Bay's "Pain and Gain" - for which he bulked up to 213 pounds - Mackie actually aimed to get even bigger for the role of Falcon ("he's written like an MMA fighter," he told me) before that idea was quickly nixed by the powers-that-be.

"With 'Pain and Gain' I was 213 pounds, and that was just massive eating and working out," he said. "With this, I wanted to get up to 225. Cause the Falcon is written 6'2", 240. ...So you know, with film you can get halfway there and look like that, but when I told them what I wanted to do they were like, 'no no no!'... So I just...I came down to like 190 and just shredded up. No fat."

But enough about Mackie's workout routine - I wanted to know about the bird. Will there be one? Indeed, for much of the Falcon's history in the comics he fought alongside Redwing - a winged compatriot telepathically linked to the high-flying superhero.

"No, the way the Falcon was created...he was created in three incarnations," Mackie answered. "And we went with the more military aspect of him as opposed to the superhero earlier aspect. So there is no bird."

So no on the bird, but yes on Mackie's co-stars Frank Grillo and Emily VanCamp, who joined us to chat about their characters, Crossbones and Sharon Carter/"Agent 13." For his part, Grillo appreciated that Crossbones (real name: Brock Rumlow) had no superpowers to speak of.

"This is a guy who has very little fear, very little fear and has a mission and is kind of...has tunnel vision when it comes to the mission," he told me of the character. "And whether they're superheroes or not, it's irrelevant to him. He does what he does. That's why I...I mean, when I first met with them and they explained to me who the character was and then I went and kind of found the origin of Crossbones and Rumlow...it really excited me, because I don't have superpowers. And yet I kick the shit out of a lot of superheroes."

"He gets his ass kicked in the movie by everybody! By everybody!" exclaimed Mackie at one point.

"By everybody, including Emily?" I asked.

"It's interesting you should say that," responded Grillo, looking at VanCamp.

"I can't say anything," she said.

"Can't say anything, but it is interesting you should say that," he continued.

Speaking of VanCamp's character, in the comics Carter is a highly-trained secret agent code-named "Agent 13" who is also the on-again/off-again girlfriend of Captain America. So will we be seeing some action from her by the end of the film? VanCamp wasn't saying, but based on her cryptic answer I'm gonna go with "yes."

"Listen, that part I can't really tell you," she said coyly. "What I will tell you, in this film we're really just introducing this character, so we don't learn much about her, Captain America doesn't learn much about her, it's just...it's just a beginning of what could be for who she is. So we meet her and she's living next to Captain America, and that's the extent of what I can say really. But there are, you know, a couple surprises here and there."

Like, say, doling out a beating to Crossbones?

"Captain America: The Winter Soldier" hits theaters on April 4, 2014.