BEVERLY HILLS — When Laurie Metcalf decided to be an actress, the world lost a terrific secretary. The woman who struck gold as Roseanne’s younger sister on “Rosanne,” and later became Sheldon’s Bible-thumping mom on “The Big Bang Theory,” somehow missed her calling.

“I’d always supported myself by being a secretary. I was a very good secretary all through college, typed 90 words a minute,” she says, seated in a meeting room at a hotel.

“Then for the first few years that we were starting the Steppenwolf Theatre Company, we were paying ourselves nothing and charging $3 a ticket, so we all had day jobs. So I was always a secretary… and I loved it. I loved being behind the desk and having your day’s work in front of you. And at the end of the day, you’ve done it, and it’s over in this pile over here,” she says, patting an imaginary stack of papers.

“There’s something really satisfying about it. There’s a groundedness to it that you don’t get in acting sometimes where you’re at the whim of somebody else — either getting a job or being directed — you’re not in control all the time like you can be behind a desk.”

Metcalf has chosen to be out of control in more ways than one. Not only is she starring in the second season of HBO’s edgy medical comedy “Getting On,” which returns Sunday, but she’s also starring in the CBS sitcom “The McCarthys.” Couple that with being a single parent to four children, and she has her work cut out for her.

It’s been five years since she graced the TV scene, because she’s been doing theater, which she acknowledges was her first love. In fact, Metcalf was painfully shy as a child and began studying German and anthropology and flitting among majors in college when she met some would-be actors who changed her life.

She joined fellow students John Malkovich, Gary Sinise, and Joan Allen in the Steppenwolf Company. “I never would’ve pursued acting as a career had I not done it with a group, because I was too shy,” says Metcalf, dressed in a draped, black knit jersey dress.

“I was still shy at that time — I’m not anymore — but I don’t think I could’ve done the rejection on my own. But in a group, that’s how we came up through the ranks as a group, or at least I did. I had that built-in support system, and that definitely changed my life.”

Married to fellow actor Jeff Perry (“Scandal”) at the time, she says, “When Jeff and I were together, we were making $100 a week, we could live on that in Chicago, but I’ve always been the breadwinner.” They have a daughter, Zoe, 30, who is also an actress.

Metcalf, 59, is divorced from her second husband, actor Matt Roth, with whom she has three other children, ages, 20, 14 and 9. Laughing at the spread, she says, “I guess I was thinking I had the resources and I had the time, there just should be more kids around. … That right there is a testament to how my mental health is.”

Those nine years on “Roseanne” were perfect for an ersatz soccer mom who dabbled in crafts, she says. “Thanks to TV roles, I was able to have a really great family schedule for a lot of years, Monday through Friday, weekends off, summers off. It’s like a teaching job. Wonderful. It’s the best schedule an actor can have if you have a family. There’s no traveling. It’s right here, so it’s perfect. Lots of those years were really easy that way. But then that work dried up, and I wanted to do theater anyway. Then I started this weird business where I was going away three months at a time, and they would come visit back and forth,” she says.

“That was tough at first, but you get used to it. In a way it’s kind of fun because it’s like, ‘Mom goes to New York, she’s going to be there three or four months, and then you guys are going to come out for a couple times for a few weeks and we’ll do EVERYTHING.”

Though her timidity was inhibiting at first, she’s overcome her shyness, says Metcalf. “I’d hidden behind (roles) long enough,” she says. “I like to depend on scripted words, so doing interviews has always been hard for me because I just like to interpret. I feel that’s my role: I like being the interpreter through to the audience. Being in it for so long has given me a little more confidence.”

She says even serving as the mom’s voice in the “Toy Story” movies has solidified her reputation. “I ended up doing the cream of the crop in some of these projects,” she says, smiling.

“I feel that way with ‘Getting On.’ That show is lightning in a bottle. I recognize how rare these things are. The quality, it’s not everybody’s cup of tea, it won’t ever be. And then the chemistry of the people involved (is ideal.)”

Though she’s suffered her failures, Metcalf says she never tires of the job. “I still have a passion for it, and I’m very lucky that way because sometimes it burns out,” she snaps her fingers.

“I’ve seen it burn out in friends of mine. They say, ‘I can’t imagine doing theater anymore. It’s too hard.’ But I think that’s the only place I feel energized. And my favorite place to be in the world is in a rehearsal room.”