Before Daredevil," he had to take a little punishment of his own.

No stranger to high intensity Hollywood roles -- including "The Walking Dead" -- Bernthal's also an accomplished boxer in his increasingly-scant spare time. And in order to get himself most fully into the headspace of Frank Castle, the iconic anti-hero whose high-caliber mission of vengeance often brings him into conflict with more moralistic crusaders like Matt Murdock, the actor's willing to go as far as possible to bring his character to life.

Moviefone: One of the things that's interesting about Frank Castle is that he seems to resonate deeply with comic book fans. Tell me how the passionate following for The Punisher has influenced your take?

Jon Bernthal: It's enormously important to me. Look, you start with the comic book audience. The comic book audience is a group of people I'm very familiar with. They're incredibly passionate, they're incredibly intelligent, and they can be incredibly loyal. I think that when you read a comic book, you're forced to infuse so much of your own imagination while you read. I think what happens -- the result of that is people have a real sense of ownership of the character. So I get how much this character means to so many people.

On a different level, the fact that this character has resonated so much with the law enforcement and military community, that means everything to me. There have been guys that have gone into battle for this country with The Punisher logo on their body armor, on their equipment. There's guys who have died for this country with that logo on their equipment. That means everything to me.
What's the most challenging or demanding part of the role for you?

You've seen [the first season]. They're doing movie quality fighting on a TV schedule. So it's an incredibly physically demanding job. The fights are intricate, the fights are physical, and we're always racing the clock. Physically, each episode was difficult in its own way.

I think that this character requires diving in to a very, very deep -- very, very dark -- place, and living in it, something I did for a long time. I've said before, there's no way I could tackle this role, or attempt to tackle this role, if I wasn't a husband and a father. Until you know what it's like to love something more than yourself, you can't begin to understand -- at least I couldn't begin to understand what it would be like to lose that love, and to lose people that mean more to you than you do.

You said you're a very physical guy, but what did you get really good at as a result of this role?

I'm a rehearsal whore, man! I'm just really, really into rehearsing and understanding, with fights especially. So for me, I really look at the way a man fights. It's so revealing about character. It's really important for your portrayal of the character to see how he fights, how he reacts in a fight, how he reacts to pain, how he reacts when the different sides are unmatched.

I think there's no lying in fighting. It reveals everything about a man, and I know that from my own fighting experience from boxing. For me, I think what I got better at was trusting the process with Eric Linden, my unbelievably talented stunt double, and we really sort of figured out how to take a fight. A movie-quality fight, an unbelievably ambitious movie-level fight -- and shoot it in one night, and learn how to say, "OK, this is what Eric does good, this is what Jon does good. This is how we all work together."

Once you got the role, you had strapped on a pretty heavy backpack and did some walking around New York to get into the headspace of the character. How did that help?

That's just weird actor crap, man. I don't really have a rhyme or reason for what I do. It's like, how are you going to spend your nights? In the beginning, when I was trying to find this character, I felt that loading up my backpack, putting a ton of weight in it, and just walking through Brooklyn and Manhattan would just be a good thing. Just to play with the character in your head.

It's sort of a method that sounds goofy talking about it, taking the character out to dinner, going to dinner in character and doing a whole night in character, going into different places. I just don't think that this is the kind of thing where you can be at the bars and the nightclubs, and be eating at nice restaurants, and then go step on set and be in that darkness.