Veterans were crucial to the making of The Punisher. According to showrunner Steve Lightfoot, the Netflix series made it a point to utilize veterans both in front of and behind the camera in order to create a more authentic, grounded experience.

"We did a lot of research and we talked to people and we tried to get that right," Lightfoot said during a set visit attended by CBR. "I mean, it was very important to Jon [Bernthal], who has huge respect for the military, as do I. It was very important to us to try and get that right. So the fact that people said we have was hugely important to it."

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"It was funny last year, because the most nerve-wracking scenes for me were those scenes I'd written in the vets' group, where as much as we could we used real vets to play the guys in the circle -- you know, the extras and what have you -- and I was terrified when we got to the end of some of those speeches and some of those scenes that they'd all like threaten to walk out or call bullshit and actually they were incredibly supportive," he continued. "So we hoped early on we'd gotten it right and we never talked about outreach or anything like that, but in the show we try where we can, as much as we can."

"We've cast quite a few vets this season, both as extras and as characters in the show," he revealed. "We just try and listen to those guys and make it resonate. I mean, the other thing you'd have learned, if you've meet one vet, you've met one vet and I think you can't generalize that experience, but as much as we can, we try to do it justice."

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Billy Russo actor Ben Barnes recalled his work with veterans on the Netflix series. "We did actually have some veterans that we worked with through the first season who kind of stayed in contact, so we had them available to ask for of questions too," he shared. "But there's definitely something that obviously with having Flo[riana Lima] playing Krista, who's my psychotherapist, in the story. That was kind of interesting thing that we kind of looked at some interesting things, which I know I'm not allowed to talk about, but there is some specific things, specific sort of veteran stuff that we talk about, which I talked about with psychotherapists and psychiatrists and sort of read a lot about why we were doing this thing that we're doing.

"So that was kind of cool too, to have it really be kind of grounded in something very specific and modern, too -- something quite modern, in terms of how we encourage veterans to talk about their experiences now, not what they did in the 70s," he continued. "So that was kind of interesting, to be -- even if we're not saying, necessarily, anything about it, at least we're trying to sort of represent it, representing these sort of psychological traumas in a modern light."

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Frank Castle himself Jon Bernthal also shared his experiences working with veterans on The Punisher set. "It's the best part of the job is just the friendships. We're doing a scene tonight -- again, I can't tell you shit about it -- Gunnery Sergeant Freddie Joe Farnsworth, we're doing some crazy Marine stuff tonight," he teased. "You know, the relationships, that the fact that those guys kind of open up to me -- I think anytime a vet opens up to you, not just sort of welcomes into their world or teaches you how to shoot or use a weapon or teaches you how guys talk to each other -- but when they really start to open up and talk about their experience, that's a treasure. Like I really cherish that and I appreciate that and I really try to connect to it and put it into the work."

Arriving on Netflix in January, The Punisher Season 2 stars Jon Bernthal as Frank Castle, Ben Barnes as Billy Russo, Amber Rose Revah as Dinah Madani, Deborah Ann Woll as Karen Page, Jason R. Moore as Curtis Hoyle, Josh Stewart as John Pilgrim, Floriana Lima as Krista Dumont and Giorgia Whigham as Amy Bendix.