Illustration: Rob Kelly

If belligerent geek Dwight Schrute from NBC’s The Office quit the paper business, grew out his hair and planted himself behind a drum kit, you’d get something like Robert “Fish” Fishman, the character Rainn Wilson plays in the new comedy The Rocker. The film, which is being plugged incessantly in advance of its August 20 release, portrays Fish as a pot-banging sad sack, still bitter two decades after being fired by a hair-metal band minutes before they signed the record deal that would make them famous. He gets a second chance at stardom when he is cajoled into joining his teenage nephew’s up-and-coming emo band. It’s the perfect first lead role for Wilson, 42—although you’d never know it to talk to him.

Does the pressure inherent in being the film’s star ever freak you out?
Me? I never worry about anything. That was sarcasm. I had a lot of different worries. Is the movie going to be any good? Am I going to suck? Are people only going to want to see me as Dwight? What does my hair look like? Am I getting too fat? What is that weird rhythm my heart seems to be making? I wonder if I have a degenerative heart disease.

Did you ask Steve Carell for advice?
Yes, I did. I slept on his doorstep for three nights in a row. His wife fed me scraps. Finally he came to the door and said, “What?!?” And I was like, “Oh, Steve—please tell me how to star in a movie!” And he showed me the way. He was my Yoda.

Considering the nature of your character, it’s fitting that Pete Best, the original drummer in the Beatles, has a cameo.
What a cool guy. He has a great sense of humor. Seems very much at peace with his past. It was a pleasure having him around. We had a little scene, but it was cut and will only be on the DVD. That’s a little bit ironic, isn’t it, for Pete Best?

Let’s coin a new euphemism for the drums here. Ideas?
Meerkats, as in, “munchin’ on the meerkats.” Or what’s that game? Whac-a-Mole? How about “whackin’ on the moles”?

Perfect. In one scene, Fish plays the moles naked.
Thanks for noticing.

Did you really take it all off?
I had on what they call a modesty pouch—a little satchel with a drawstring around my genitalia. It didn’t leave much to the imagination. Naked drumming’s not something I would recommend. It can get very sticky on the drum stool. Human buttock and leather grinding together is one of the strongest adhesives known to man. It’s like Krazy Glue.

Did you already know how to play drums?
No, not at all. I went to a drum coach, and it was a lot of fun. Not only learning drumming, but then learning the art of heavy-metal drumming, which is a whole nother world to itself. They’re Vegas showmen behind the kit. Stick tricks. Pumping up the crowd. Cueing pyrotechnics. Finding the cute girls. They are the dynamo contingent of the band.

At times it did seem like you were channeling Tommy Lee.
Well, he would not need a modesty pouch. He would need a modesty gunnysack.

Enough about drumming. Based on your name, I take it your parents weren’t exactly conventional.
Yeah, my parents were on the bohemian side of hippie, living in a houseboat in Seattle in the late ’60s. But I got lucky because my mom—true story—wanted to name me Thucydides, after the Greek historian. Look it up, bro. He’s the author of The History of the Peloponnesian War.

Why are there two ns in Rainn?
The extra n is for extra nookie. Uh, I have no idea. I don’t understand anything my parents did or do. They’re weird.

Speaking of weird, John McCain is an avowed fan of The Office. Does that mean you feel obliged to vote for him?
I guess so. Yes, I’m going to have to. I’ll be one of eight people in California voting for him.

The Rocker opens Aug 20.