It's a long way from the Brigham Young University campus to the sewers beneath New York City, but it's a journey Cam Clarke has made.

The former BYU student is the voice of Leonardo, who, along with his fellow Teenage Mutant Ninja Turtles, resides in a Big Apple sewer in the animated series.Being the voice of a world-famous turtle wasn't exactly what Clarke, a member of the King Family, had in mind when he enrolled at BYU in 1979. After a "fairly normal" semester as a "zoobie," he was asked to join the Young Ambassadors performing group and spent part of his second semester touring with the group in China.

"Since I knew what I wanted to do, there was no reason to be in school," Clarke said. "So I headed for California to try my luck."

In Hollywood, Clark tried everything from modeling to commercials as well as acting. Almost by accident, he began doing voiceovers.

"It was pretty much a Cinderella story from there," he said.

He started out doing the sound dubbing for TV shows - the police dispatcher's voice on the radio, the hospital P.A. announcer, the people in the background. Soon he had an agent, a voice coach and was getting more and more work.

"It was pretty much 1, 2, 3 for me," Clarke said. "It just started snowballing until now I work every day doing everything from cartoons to advertisements to movie trailers."

Among his cartoon credits are Snoopy, Denver, the Last Dinosaur and the California Raisins.

"I got that after some discussion about whether the Raisins were black or white or purple," he said. "We decided they were purple so I was allowed to be in the show."

Then, in 1987, came the offer to do "Teenage Mutant Ninja Turtles."

"I thought, `Oh please. Ninja Turtles, excuse me?" he said. "It was just another show. So many shows start and never go anywhere.

"You never know what's going to happen. The best ideas fall flat and the screwiest things take off."

For the uninitiated, the Turtles were transformed by "radioactive ooze" into crimefighters. They don't possess super powers but they do possess a sense of humor. It's not uncommon to have a Turtle turn to the screen and say, "Don't try this at home, kids."

Clarke isn't one of those method actors - or is that method talkers? - who tries to "become" Leonardo.

"To me, it's just acting. Actually, it's just playing. It's a bunch of grown-ups sitting around playing. We're doing funny voices and getting paid for it."

"Turtles" is so hot that, even though it is continuing a successful run in syndication (seen locally weekdays at 7:30 a.m. on Ch. 13), CBS picked up 13 new shows for its Saturday lineup (8 a.m., Ch. 5).

"I think one of the things that helped us is that we were in syndication and the powers that be give you more power to create," Clarke said. "While it's a show kids like, there's also some . . . humor the adults will get too. It's like the old `Rocky and Bullwinkle' shows. You liked it as a kid, and when you watch it as an adult you say, `Hey, this is funny.' "

Clarke is a member of Famous Phone Friends, a group of voice artists and teen idols who call sick and troubled children across the country.

"For us, it works great on the phone," Clarke said. "But if a parent wants us to do it (the voice) in public, we have to say no because the kid just doesn't get it."

The one time he broke his own rule against using Leonardo's voice in public just reinforced his resolve never to do it again. He approached a 6-year-old boy decked out in Turtles paraphenalia.

"Guess what, I'm Leonardo," Clarke said.

"Oh yeah? And I'm Donatello," the boy said as he turned on his heel and walked away.

Clarke is in Utah this week to appear in BYU's Homecoming Spectacular. "I'm trading my green turtle suit for a red crab suit and doing Sebastian's `Under the Sea' number from `The Little Mermaid,' " he said. "It should be a lot of fun."