From frowning to flatulence, Jack Black uses every faculty to generate his particular brand of comedic action. And nobody is safe in his presence.
We're in a New York guitar studio where the comic actor is strumming a Gibson acoustic with co-star and best friend Kyle Gass. Suddenly, they explode into a "Nightline" rock anthem that starts with "Want the scoop/look at the poop/Try to figure out some things ..." and finishes with "It's Martin/kicking up the news jams."
It's a funny, harmless lyric and consistent with Jack Black's zany yet empathetic persona -- an actor who might be suffering eyebrow twitches and attention deficit hyper disorder, but is warm hearted and harms nobody in the process.
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Black and Gass are currently on tour promoting their new movie, "Tenacious D: The Pick of Destiny," a film about their cult rock band that they formed 12 years ago after meeting as budding performers at the Actors' Gang in Los Angeles.
Black, who looks much younger than 37, says he's more proud of this film "than any other film I've been in." And he's been in some pretty big movies.
Black's big break came in 2000 when he won a part in "High Fidelity" as the acerbic record store manager who refused to sell what he deemed to be mediocre music to his customers.
But he almost didn't take the part. As Black explains, "That was the biggest part I'd got in a film, and I was very nervous. I turned it down initially because I thought ... 'what if people don't like me? I just rather keep the little piece of pie that I have over here.'"
But he was persuaded to ignore his insecurities, principally because director Stephen Frears kept offering more money. The result was a movie that catapulted Black out of obscurity. Many critics thought this performance stole the show from established stars, like John Cusack who also appeared in the film.
"School of Rock" soon followed and was a smash. Even the DVD sold out. It allowed Black to join that rare breed of comic actors who can carry an entire film on their own shoulders.
"Nacho Libre," released earlier this year, was more of the same with Black playing the role of a chef in a monastery-come-orphanage for children in Mexico. He decides that the only way to improve their diet is for him to become a wrestler and earn cash to buy better produce.
But again, Black suffered anxiety about whether he could pull it off.
"I was freaked a little bit with 'Nacho Libre' because I was playing someone from another country. I've never done that before and I was like, 'what if the people from that country are offended and they're thinking, hey, is he making fun of us?' So, I paid extra attention to getting the accent right and, you know, doing some research and ... I felt good in the end that I did it."
Black's insecurities have manifested themselves in other ways. He says that he has a combined form of obsessive compulsive disorder and ADHD. "I have a little bit of OCD and ADHD. So I'm OACDH!" He also admits that these symptoms help inform his performances.
But now, having become this silly yet sensitive actor, he's decided to indulge his passion for rock music and his own band Tenacioius D. And here's where the trouble may start: having built a reputation as a family entertainer, the content and dialogue of the new film is overtly, almost obsessively sexual.