Petersen, 50, belongs to the old, quixotic, let's-put-on-a-show-in-the-barn school of performing. His fondest showbiz memories are of running a modest theater company in Chicago for 16 years, till 1995.
Of course, he also happens to be the star and an executive producer of prime time's No. 1-rated series, CSI: Crime Scene Investigation. But he may be the only TV producer who doesn't go over the Nielsen numbers with a fine-tooth calculator.
"When we get involved in the ratings," he says, on the phone from his home in Los Angeles, "then we're doing the network's job. We need to focus on our work."
When CSI debuted on CBS in 2000, Petersen didn't expect the science-centric and graphically visceral show about forensic technicians to become a monster hit, or to spawn one spin-off (CSI: Miami), with another (CSI: New York) on the way. "We thought we would have a niche audience of loyal viewers like X-Files or West Wing. But we have a huge audience that crosses all kinds of boundaries. It's unique. It's bizarre."
Not that he doesn't think CSI deserves its success.
"I assume that part of it is due to the quality of the show and the characters and their chemistry," he says. "People like the way it twists and turns on itself. Each week is a puzzle, a really well-done puzzle."
And let's not discount the possibility that CSI's popularity has something to do with its leading man.
"When I started CSI," says Carol Mendelsohn, one of the show's eight executive producers, "I told my girlfriends I was working with Billy. They all said, across the board, 'Can I come to the set?' You start with the sheer magnetism. Plus he's so handsome."
If you visit any number of chat rooms, you can't help but notice a lot of romantic speculation about Petersen's character, Gil Grissom. That's a little surprising because, let's face it, the guy is a workaholic wonk with an affinity for insects.
"I wonder how many women would want to wallow around in maggot farms at night," Petersen says, "because that's really all Grissom could give them. Women think, 'Boy, could I make improvements on this guy,' and of course Grissom is scared to death of any improvements being made."
Petersen's penchant for inhabiting two universes simultaneously began when he was growing up in Evanston, Ill., a Chicago suburb. He was a fanatical jock who also enjoyed the musicals his mother took him to.
"Sports were everything," he says. "I'd play them all day, and at night I'd listen to Camelot."
He was the youngest of six, a bonus baby whose closest sibling was eight years older. "My dad's family is Danish. My mom's family is German. She's the oldest of 12 from Duluth. We have these family reunions in northern Minnesota and there are 250 of us up there."
An indifferent student, Petersen dropped out of high school in Evanston and eventually finished up in Boise, Idaho, where he had gone to live with one of his brothers.
He enrolled at Idaho State University in Pocatello to play football. Along with some teammates, he was encouraged to grab some easy credits by working on sets for the theater department.
That's when the drama bug bit.
"I loved the people who did it," he says. "I loved the gypsy element of it."
He worked for a time as a logger. "I had read [Ken Kesey's novel] Sometimes a Great Notion. That lasted three months. Then I realized it was way too hard for me."
Finally he moved back to Chicago, and in 1979 started the Remains Theater Ensemble with fellow actor Gary Cole.
"I spent my 20s with John Malkovich, Gary Sinise, John Mahoney, Laurie Metcalf and Aidan Quinn," he says. "In Chicago back in the '80s, we had this amazing group of talent that may never exist again in American theater. I can't turn on a TV show or go to a movie without seeing one of my friends."
Back with a vengeance
Ever restless, Petersen took a year off from performing, working for a tree service in Evanston. When he came back, it was with a vengeance. A casting director had caught his stage work, and in short order, he starred in director William Friedkin's 1985 film To Live and Die in L.A. and Michael Mann's 1986 Manhunter. The latter, based on a Thomas Harris novel, introduced the character Hannibal Lecter and was recently remade as Red Dragon.
"All of a sudden," Petersen recalls. "I was the lead in a Billy Friedkin movie and a Michael Mann movie and I hadn't even been in Los Angeles. That just doesn't happen. You're supposed to go to Los Angeles and spend years working your way up."
The actor got glowing notices in both films, and was deluged with offers. It seemed his film career was about to skyrocket. But Petersen aborted the launch.
"They came after me with this cop movie and that cop movie, but none were as good as the two I had just done. I figured unless you come up with something brilliant, all I'm going to be doing is repeating myself."
It wasn't that stardom eluded him. Petersen eluded stardom. He refused to hire an agent, and accepted roles only if they interested him, not if they had commercial potential.
Following the peculiar beat of his own drummer, he got to portray both JFK (in The Rat Pack, a 1998 cable film) and his father, Joseph Kennedy (in the 1990 mini-series The Kennedys of Massachusetts). "I just have Rose left to play," he jokes. "When they do her story, I'm going to audition for it."
Over time, he became more and more disenchanted with the movie business.
"The studio system had become uninteresting to me. It was a revolving door with different corporations calling the shots. The world of independent films was great, but it was hard to get anything distributed. You may work on something for three years and never see it make it to the screen."
Fed up, he began to consider a TV series.
"I'd been talking to [CBS czar] Les Moonves for years. He and the guys at the other networks had been after me constantly. But I couldn't find anything I wanted to do."
Then an unknown writer named Anthony Zuiker, who had been driving a luggage tram between casinos in Las Vegas, pitched the idea of crime-scene investigators obsessively sifting through trace evidence.
Petersen knew that starring on TV would change his life. "Ted Danson was a friend of mine, and when he was on Cheers, taking him out was a huge deal. People jumped all over him.
"When you're in movies, people may recognize you, but they leave you alone. But on TV, you're in their living rooms. You're far more involved in their lives."
In December, he added the executive producer's hat, which involves him in script approval and production logistics, making him busier than ever.
Unlike other TV stars, who will try to squeeze a movie into the hiatus between seasons, Petersen tends to lie low during his downtime from CSI. "My goal is to find enough time to spend with my family and my golf game."
That family is growing. Petersen married Gina Cirone, a Chicago schoolteacher, in the summer. His only child, Maite, 28 (from an early marriage to Joanne Brady), recently gave birth to a son, Mazrik William. Her husband is Philadelphia native Carl Della Badia.
"I've got a wife, a dog, a cat, and a grandson, all of which is good," Petersen says. "Personally, I haven't been this comfortable in a long time."
Professionally, he's glad to be playing Grissom, a character with enough crevices to keep him interested.
"I'm still learning stuff about him," he says. "I wanted to create something that would be interesting for me day in and day out, because I was always deathly afraid of doing the same thing week after week."
Spoken like a true saddle tramp.
Contact staff writer David Hiltbrand at 215-854-4552 or email@example.com.