PASADENA, Calif. — He could’ve been a veterinarian like his dad, or a classy waiter or even a forest ranger. But Robert Knepper’s passion was acting which was ignited when he saw “Ten Little Indians” as a kid at the local community theater.

“When I was growing up in Ohio my mother did props at the Maumee Civic Theater … I remember sitting down in front and there was this actor named Jim Rudes who was playing the judge. … It was like I was inside the play.”

Staying inside the play became a life goal for Knepper, 53. “The secret for me was I never had something I could fall back on,” he said.

“Because I decided I was going to be an actor, I went to Northwestern, I was so gung ho to get into professional theater in downtown Chicago … I auditioned for a play my last year in January, and I got it.

“I thought, ‘Now what do I do? I’m in a professional play, but I’m still in school.’ I called up my dad and said, ‘I’m dropping out of school.’ Four years – he paid for it all. He was so mad at me. I said, ‘Dad, I don’t need a piece of (expletive) pigskin to prove I can act. I’m not going to be a teacher. I don’t need a diploma.’ I wished I’d gotten one, but I kept thinking, ‘I don’t have anything to fall back on.’ ”

Years later Knepper was to regret that decision, but he went on to star in shows like “Prison Break,” “Carnivale,” “Heroes” and his latest, the CW’s thriller “Cult,” which probes the excesses of fandom. This show marked a coup for Knepper, who essaid two roles – an actor and the character the actor plays on a TV show.

Acting proved fruitful until he married and had his son, Ben, 10 years ago.

“Tory, my then-wife, said to me, ‘You’ve got to bring in more money. We got a new baby. Either I have to get a job and bring in more money, or ...’ When I first moved to New York I worked in a restaurant and I loved being a waiter,” he said, shifting in his chair.

“I was tired and by the time I got to the theater at night – everything was raw. And it was great. I loved people. I always made 20 percent from everybody I served. I was as particular as a waiter as I am as an actor.”

He told his wife, a former casting director, he would find something else to do. “I said, ‘Be home, be the mom. Let me figure it out.’ So I said I just can’t wait tables so I thought I got to do something I love. What do I love besides acting? I love nature because I grew up on farms and I grew up near forests … I love nature. That’s not going to get me any money.”

He decided to try to teach acting and applied at UCLA. But because he had no diploma he was rejected. Instead he was offered a job instructing adult classes for $50 a class.

“I thought that’s not going to cut it. So I thought what’s my second thing? Nature. I thought, ‘I’ll be a park ranger.’ So I drove up to Will Rogers State Park and put in an application to be a park ranger. I thought, ‘I’d cleaned my dad’s dog cages growing up and I know what it’s like to clean toilets, so that’s probably what a ranger does most of the time – and I think I might look good in that hat .’“

The day after he submitted his application he was called for “Prison Break.”

“It was a Friday and we started shooting on Monday in Chicago. I was never so close to giving up my love … Nothing against those professions, I was just giving up my heart. And I called UCLA and I said, ‘I’m doing this new show. It’s not a safe bet. A lot of shows don’t go. I’m supposed to start teaching with you in January, but I don’t think you should put me on the syllabus because it might not work out.’ ”

Laughing, he said, “I never heard from Will Rogers Park, never heard boo … We shoot all episodes, June, July, the show’s on, and it explodes. In November. I hear from Will Rogers Park. They said, ‘Robert Knepper, we have a job for you but we don’t think you’re going to need it.’ I started crying on the phone and said, ‘You have no idea how happy you make me feel because I was totally willing to be a park ranger for you because I love Will Rogers Park and love nature so much, but I’m very glad I don’t have to do that.’

“It went from me begging them to scrub their toilets to the end of the phone call when I said to them, ‘Anytime you need me to help out with fundraising, I would love to help.’ And that’s what I try to do because you never know what’s going to happen.”

‘Celebrity Apprentice’

Trace Adkins is one of the celebrities returning to NBC for the “All-Star Celebrity Apprentice” on Sunday. Each contestant works for a charity of their choice and for Adkins, it’s the Red Cross. He has good reason. “In June of 2011 my house burned down, and I was in Alaska doing a show, and the Red Cross was there,” he said.

“The Red Cross showed up, took care of my family, and it really touched me. And I was ashamed of myself that I didn’t know that the Red Cross responded to house fires. I thought they were grand-scale natural disasters, and that was about it. And I was ashamed of myself that I didn’t know that they responded to 70,000 house fires a year. And the fact that they were there and took care of my family when I couldn’t be there, I just felt like I owed them.”

Adkins said for a month he resisted returning to the fiercely competitive show. “The first time I was on ‘The Celebrity Apprentice’ was one of the most stressful periods of my adult life, and I didn’t want to come back and do it again. So it took my house burning down to get me to come back,” he said.