Mark Zupan has been called by Entertainment Weekly the year’s most surprising action hero, but probably no one is as surprised as he is. A quadriplegic since the age of 18, Zupan is one of the stars of “Murderball,” a documentary about wheelchair rugby that proves hard-hitting in more ways than one. And it’s made him an instant celebrity.

“I knew it was going to be something, but definitely not this!” he said in a recent Dallas interview. “This whole thing is weird. It’s been weird but it’s been kind of fun. I mean, we’re going to do Leno on Friday. [We did] Regis & Kelly. We did a ‘Jackass’ episode. You’re sitting there [thinking] ‘Wait, is this really happening?’ And you’re like, ‘Wow.’” The change began at the Sundance Festival, where “Murderball” was first screened last winter (it won the Documentary Audience Award and a Special Jury Prize for Editing). “Sundance to begin with,” Zupan recalled. “To see Sundance from the inside out…you go to a party and it’s like, ‘Yeah, come in!’ It’s like, ‘What? This really works!’” And when told he’s a celebrity now, Zupan demurs: “Well, I don’t know about that. A celebrity? My face is on a couple things.” Still, he can’t get over being recognized during a recent trip to New York. “It’s very, very strange from everyday life,” he admitted. “Everyday life for me was wake up, go to my engineering job [he works at C. Faulkner Engineering in Austin, Texas], go to the gym, turn around, come home and go to bed. Now, it’s ‘What city are we in now? And what the hell are we doing?’ But it’s been fun.” It’s even been enjoyable, he said, to go back to his job whenever his touring schedule permits. “It’s like an hour and a half of just getting ragged on,” he said. “’So, you decided to come to work, Mr. Hollywood!’ But it’s fun.”

Of course, Mark Zupan’s idea of fun includes bashing his fellow quadriplegic players with abandon as they all maneuver their specially-constructed chairs around the court to win matches for Team USA in international competitions. He’s been playing the sport competitively since 1996, after a car accident (he was thrown from a truck being driven by his best buddy Chris Igoe). “I found it in rehab, about a month after I was hurt,” he said. “But I didn’t play competitively until ’96 in Atlanta. I was in outpatient rehab in Atlanta, and one of my therapists whose boyfriend at the time played said, ‘I think you’re going to be good at this–why don’t you try?’ And one thing led to another.” What it led to was a spot on the U.S. teams in the world championship matches and the 2004 Paralympics in Athens.

But wheelchair rugby hasn’t been in the public eye–something “Murderball” may change. And it all started, Zupan said, with an article on the sport by Dana Shapiro in a Phoenix newspaper. “He and Jeff Mandel always wanted to make a movie,” he explained, “but they didn’t know how. Henry Rubin was brought in, because he shot second-unit on ‘Copland’ and ‘Girl Interrupted,’ so he knew how to shoot, they had business sense, and together it came. They came to Sweden, started filming just random people, just filming the game, and they said, ‘You know what? We have subject matter–let’s run with it.’ And the rest, I guess, is history. None of us had any idea what you were going to see on that screen–no idea. You saw the passion behind the filmmakers–they were very, very passionate. I think they saw our passion in the game and we saw their passion in the process.” Now that he’s seen the movie, Zupan believes that it can have a positive effect: “I think hopefully after this film not only will it raise awareness of wheelchair rugby, but it’s going to raise awareness of [all] wheelchair sports.”

But what Zupan especially liked was the fact that it portrayed the players realistically. “When I first saw it, I said, man, they made a pretty spot-on film, because they captured who we are,” he said. “It wasn’t a ‘woe-is-me gimp movie.’ You have your grumpiness, your happy times–it’s just a great representation of life. This is how we are. We’re athletes, we train. We’re as passionate as the Olympians or anybody else who’s in sports. We’re going to bust each others’ balls, we’re going to have fun. We’re normal guys, and that’s what was cool, that you can finally see that depicted on the screen. Hopefully it will teach one person, make somebody say, ‘Hey, I’m going to treat these guys just like a normal person–I’m not going to baby them or think that they’re different, or think that they need help.’ If we want help, we’ll ask. Just don’t assume–that’s the most annoying thing that could ever happen. And I think it’s just good publicity for not only the movie but for guys in chairs and ladies in chairs. We’re normal people. We can sit here, have a discussion, laugh. You guys can get mad at me, I can get mad at you, and it’s just a normal [thing].”

The strong human side of “Murderball” is expressed not only in its depiction of the U.S. players as a group but especially in Zupan’s very different attitudes toward two people–his old friend Igoe and Joe Soares, a one-time player for Team USA who now coaches their bitter rivals, the Canadian squad. The animosity he feels toward the latter is a palpable part of the picture, and Zupan is quick to say that his opinion hasn’t changed, even if the film depicts how a heart attack altered Soares’ initially strained relationship with his young, musically-inclined son. “I haven’t liked him since ’96,” Zupan said. “I’ve never been friends with Joe. I wouldn’t play if he was going to be the coach of the US team.” Did seeing “Murderball” alter his feeling about Soares at all? “No,” he said. “I feel bad for his kid, but I’m sorry, I don’t like the man, I don’t think I’ll ever like the man. He has knowledge, he knows the game. I will never take that away from him. Do I think he conveys it well? No. You don’t belittle your players and say, ‘We’re here because of me.’ Bullshit. It doesn’t work that way–sorry. I have never played with him, I’ve played against him. We tried out for the same 2000 team–we both got cut. He bitched and moaned and tried to sue. I said, okay, it’s time to train again. Two different personalities. Do we both have passion? Of course we both have passion. It’s just a different way of focusing it, if you will.”

With regard to Chris Igoe, however, the movie tells a different story. He and Zupan hadn’t had contact since the accident in which Mark had been injured, but they’re reunited when Igoe comes to cheer on the US team at the Athens Paralympics, and they’ve returned to the close friendship they’d enjoyed through school. “He’s like my brother,” Zupan said.