mark wahlberg lone survivorVictoria Will/Invision/AP

In "Lone Survivor," Mark Wahlberg takes on the tough task of portraying Marcus Lutrell, the one Navy SEAL who survived a harrowing gunfight with the Taliban that claimed the lives of his entire team.

The actor talked to Moviefone about the responsibility he owed not only to Luttrell but to the families of the men who died on the failed mission and the rest of the SEAL community. He also talked about how he personally rescued the project after the studios decided it wasn't commercial enough and why he didn't read Luttrell's book before making the movie.

Moviefone: This movie was pretty tough to watch. How tough was it to make?

Mark Wahlberg: Yeah, it was difficult at times, but we all knew how important it was to tell the story and that helped us get through it.

What's your responsibility as an actor when you're playing someone who actually went through this?

It's a pretty overwhelming amount of responsibility. You have the entire SEAL community, the military community, the members of the families of all these fallen soldiers; they're expecting you to get it right. We were aware of that and we were committed to doing that. It's the first time that I made a movie that wasn't about me and my experience as an actor. It was really about the story that we were telling and making sure that we were going to get their story right. It was the same for everybody, both in front of and behind the camera. Everybody's commitment to telling the story was the only thing that was important. That was our goal.

You're playing the one man who lived, so you have the benefit of his firsthand experience. How much time did you spend with Marcus?

You know, I spent quite a bit of time with him, but it was also one of those things where I didn't want to overstep my boundaries and ask him questions that he was uncomfortable with, having to relive something. We had the source material. The one specific thing that I did want to ask him, if he was comfortable talking about, was when he was alone in the village and what that must have been like, with the inability to understand the language and the fear of the unknown. It was pretty scary stuff.

What did he tell you about that?

He told me everything. He walked me through the entire thing. Were they really wanting to help him? It took a while for him to figure out what was going on and what was happening.

Did you meet the families of the other SEAL members? What did they tell you?

Yeah. Everybody pretty much said, "Don't mess it up."

How did you first get involved with the film?

Peter approached me about it. It was one of those things where it was supposed to be at the studio for a certain price and then, for whatever reason, the decision was made to not do it. So I said to them and everybody involved, "Why don't you let me do what I did with 'The Fighter'? I'll raise the money -- we'll obviously have to do it for a lot less money. It's an intimate movie anyway. I don't think, as long as everybody makes a little bit of sacrifice, that you'll miss anything."

And you recommended Ben Foster for one of the main roles.

I'd already worked with Ben [in "Contraband"], so I was recommending him because of the bond we have and his ability as an actor.

Ben actually looks quite a bit like Matthew Axelson. Because he's the last other SEAL alive, how tough were those scenes when they know it's just the two of them left?

It's pretty heavy because you know that this really happened, and you're seeing the reaction of the SEAL guys, who are consultants, and of Marcus and everybody gets pretty overwhelmed with emotion.

Peter was saying that Marcus wasn't on set for several scenes.

Yeah, he wasn't on set for the gunfight scenes or with me in the village. Marcus would have been okay with it, but I don't think Pete was necessarily okay with it.

For those family members who have seen the film, did they tell you that you got it right?

Yes, thankfully. I was very proud. It really is a tribute to them and anybody else who's ever walked into a recruiting office and signed up to defend our country.

What reactions have you gotten from the SEAL community?

They're very proud of the movie, very proud. And these are guys who don't sugarcoat anything.

They would have told you if you'd gotten it wrong.

Oh, one-hundred percent.

You did some SEAL-type training for this role. How intense did that get?

As intense as those guys wanted to make it. We needed to look real and believable and so that was what we were doing.

There's a lot of falling off cliffs in the film. How many of the stunts did you do yourself?

Whatever they asked. Whatever was required of us.

Peter said he was actually having to talk you and the stuntmen down a little bit from going full-out because you could have really gotten hurt.

Yeah, I'm not the thrill-seeker and adrenaline junkie that I used to be, so I tried to be as cautious as possible. But I also wanted to make it as realistic as possible, so you just have to find that fine line and not cross it.

What was the most challenging part of the shoot?

Just all the elements, you're up there 14,000 feet, getting up there, being up there, the gunfights, the action. It wasn't the easiest shoot ever but it's certainly the movie that I'm most proud of.

Where did you shoot it?

In Albuquerque, New Mexico, and Santa Fe.

And that looks like the right terrain?

I've been to Afghanistan myself so, yes, absolutely.

When were you in Afghanistan?

December 2010. We flew over there commercial to thank the troops for their hard work, and I showed the "The Fighter" on three different bases there.

You had real SEALs on set as consultants the whole time.

Yeah. They were there to correct you if you weren't doing something right. And then you get to go out and hang with them and have dinner. We'd have barbecues down at the base of the mountain every day, so I got to spend a lot of quality time with them.

What kinds of things did they correct when you were filming?

Technical stuff. Movement. Not being in the right place at the right time.

When you first read the book, did you think that you would have made a different decision than Marcus did about letting their hostages go free?

I didn't read the book until after I made the movie because I'd read the script first. It wouldn't do me any good to read the book and then think, "Well, maybe this should have been in there" or "Why isn't that in there?" It would've made me a crazy person. But anybody could sit there and say, "Oh, I would have done this." It's easy to say, being a Monday morning quarterback. You're in this position, you're not trying to judge anything. We're just telling the story the way it happened on the mountain.

"Lone Survivor" opens in limited release on Christmas Day and expands in January.