During the TCA (Television Critics Association) press tour today, IGN joined a small group of journalists to chat with Captain America: The First Avenger/Captain America: The Winter Soldier screenwriters Christopher Markus and Stephen McFeely about returning to write the third film, Captain America: Civil War (and their TV series Agent Carter, but more on that later).

Naturally, with Marvel's formidable secrecy, there were few specifics they could give on the film, which -- like the comic book story it's based on -- will involve Captain America and Iron Man at odds with one another. However, they did touch on the Black Panther casting, the relationship between Tony Stark and Peggy Carter, balancing the Civil War comic storyline with the Marvel Cinematic Universe and the film's tone.The Agent Carter TV series is further establishing the bond between Howard Stark and Peggy Carter, which begs the question - just how well did Howard's son Tony know Peggy? And how might Peggy, as a potentially important figure in both their lives, impact the Tony/Steve Rogers dynamic in Civil War?Here's what McFeely has to say about Tony and Peggy and how their dynamic might play out in Civil War:"As we have not started shooting, and I’m on my fourth draft of many, that question [of who Peggy was to Tony Stark] has been in and out all over the place so who knows. So many things can shake out but we’ve had conversations and we pitched scenes. Some stay and some don’t. But we saw [Peggy] in Winter Soldier, so we know she’s around".The duo briefly mentioned their excitement over the casting of Chadwick Boseman as Black Panther, but didn't go into detail on the character, who will be introduced in Civil War.I’ll keep that one close to the vest," said McFeely, "but I’m very gratified that they went with Chadwick and that he said yes because he’s a good get."McFeely and Marcus also talked about their initial reactions to reading the Civil War storyline."There’s a depth of myth [to the Civil War storyline]," said McFeely. "People asked this earlier at our other panel, why now? Why are comic books so prevalent? Why are these movies doing so well? In some ways, we’ve become a genre that you can do well now given the world of computers and perhaps it’s also just a time in the sun. You went to the movies in the 50’s and 60’s you went to a western. So at this point, you’re going to a superhero movie. It’s taking over that same black hat, white hat myth-making surface. I don’t have a much smarter answer than that."As for how long the storyline has been on the table as a potential film, McFeely admits it was "on and off", primarily because the MCU has evolved so much since the book was written."It’s been on and off the table for a while, let’s put it that way, and it’s a challenge to do it and make sure that all the characters that we’ve established, and everyone’s established in the MCU are serviced and sound correct, right? Because there’s a difference between the characters in Civil War, which was written in 2006, 2007. The MCU doesn’t exist [when it was written]. There isn’t a Robert Downey Jr. or Chris Evans who has helped create the character so we need to make sure that that template gets adjusted and what have you in order to make sure it services these characters and not just sort of rip off their parts and make them look like them.As for the third time round writing for Chris Evans? McFeely compares him to a screen legend."I might be repeating myself. He’s Gary Cooper for me. Him as Cap is Gary Cooper. He can do a lot with stillness and because Cap is usually right and usually held up to be right, people want to be lead by him. So, that’s one of the things I like about Chris is that he brings… Remember the parts he played before this. He was uber charming. He was hilarious. He still has that. You still like him. But it’s the fact that he’s holding that back that makes you lean in to him. It’s a different chapter for him and I’m not sure any of us said, ‘That’s the perfect guy because he was the Human Torch!’ Turns out he was the perfect guy because there’s a depth to him."Captain America: The Winter Soldier had a very different tone and aesthetic from The First Avenger, but it sounds like Civil War, which will again be directed by The Winter Soldier's Russo brothers, won't be quite as big of a veer.Joked McFeely, "Every Captain America movie has a genre and Civil War is the musical! No, I think part of the reason for bringing back us and bringing back the [Russo] brothers is because Marvel is very pleased with Winter Soldier aesthetically. I think it’s a really adult movie. It’s very well made and that’s partly the texture of the movie. You can argue it’s the most realistic of the Marvel movies, whatever that is to you. I think it’s fair to say that a Russo brothers movie will stay in that vein."One journalist broached the subject of Spider-Man, and the leaked info that there was an attempt between Sony and Marvel to introduce him into the MCU in Civil War that didn't pan out. Not shockingly, the writers were tightlipped on anything regarding that situation, with McFeely grinning and saying, "I read that as well" about the reports that Spider-Man nearly appeared in Civil War. Asked what he thought as the news began to leak, McFeely simply replied, "More problems for me!" And when he was asked which side Spider-Man would have been on had he been in the film, McFeely replied, "That’s a great question! More problems for me!"Captain America: Civil War is scheduled for release on May 6, 2016.

Lucy O'Brien is Entertainment Editor at IGN AU. Follow her ramblings on Twitter. Eric Goldman is Executive Editor of IGN TV. You can follow him on Twitter at @EricIGN.