Photo: Jennifer Rocholl/Retna

‘I ’m not Daniel Day-Lewis,” says Christopher Mintz-Plasse. “I’m not a Method actor who stays in character 24/7. I just get on-set early, learn my lines, and try to be as loose and natural as possible.” But so virtuosic is his onscreen awkwardness that you might assume the 20-year-old isn’t acting at all. If the stick-thin, iridescently pale, and squeaky-voiced Mintz-Plasse tried to drink your milkshake, the milk would squirt out his nose.

Mintz-Plasse broke out in the 2007 comedy Superbad, playing Fogell, a nerdy virgin sidekick with the hilariously ill-fitting name McLovin on his fake Hawaiian driver’s license. You could argue that in producing a film that casts dweebs Michael Cera and Jonah Hill as leading men, Judd Apatow created a gaping hole in the geek continuum—a need for a supernerd, if you will. What he got with Mintz-Plasse’s McLovin was arguably the most lovably hapless dork in all of teen-sex-comedy history.

“For six months after Superbad, every script I was offered was about a nerdy character who was a virgin until the very end, when he has sex with some girl with fake breasts—cheesy, corny Hollywood stuff,” he says. “I’m still getting those roles because, look, I’m not like a heartthrob or anything. But at least they’re different kinds of nerd roles.”

Since Superbad, he’s played a Renaissance Faire–going nerd (2008’s Role Models) and a biblical-era nerd (2009’s Year One). In his latest, Kick-Ass, he plays a bratty kid whose delusions of masked vigilantism turn him into a crime-fighting nerd named Red Mist. Despite, or perhaps because of, its over-the-top violence, previewed footage received a rapturous reception at last summer’s Comic-Con. It is Mintz-Plasse’s best chance yet to convince moviegoers that he is not McLovin.

In Mark Millar’s comic of the same name, Mintz-Plasse’s character is more of a brooding goth than a high-strung dweeb. The director, Matthew Vaughn, “was looking for someone ordinary and relaxed, but I went into the audition loud and obnoxious and he trusted me with that,” says Mintz-Plasse. “He also liked that I look like I’d get the shit kicked out of me if I tried to fight crime.”

In truth, most of Kick-Ass’s ass-kicking is perpetrated by Chloë Grace Moretz, who plays Hit-Girl, a foulmouthed, weapons-trained 11-year-old who shoots and dismembers an army of goons to the tune of the Banana Splits theme. “Chloë’s mom kept joking, ‘People are going to be outraged with me for letting my daughter do this stuff,’ ” says Mintz-Plasse. (The character has, in fact, already come under fire from a parents group.)

The actor still lives with his own parents in Los Angeles. His mother, a school counselor, and father, a postal worker, keep close tabs on their son’s publicity via the Internet. For this reason, Mintz-Plasse hates TMZ. An October post reported that he coaxed a woman into removing her top at an L.A. concert and that later they left the show in his car (video evidence supports most of this). “I want to clear that up,” he says. “She was a porn star, I believe, and I did not touch her. Nothing happened between us, she was there with a guy I knew, and we walked out at the same time. My parents saw [the post] and asked, ‘What the hell are you doing?’ I apologized. I make mistakes. They understand.”

Mintz-Plasse has an unlikely sideline career, voicing CGI characters in kids’ films. He’s a Viking in the current How to Train Your Dragon, and in June, he’ll be a hairless Chinese crested in Marmaduke. “It’s really hard for me to hear my own voice,” he says, “and I’ve heard people are bothered by it.” But there are benefits: He didn’t have to audition to play a hairless Chinese crested. And the irony of that squeak’s coming from a superhero was one reason he got the part in Kick-Ass. There are rumors of a sequel, and Mintz-Plasse says he’d happily play Red Mist again, “even though the costume gave me terrible rashes under both arms.”