BEVERLY HILLS, Calif. — Ever since he was born, Welsh actor Tom Ellis has entertained an audience. “I have a twin sister, and when we were born in Cardiff at the University of Wales hospital — it’s a big training hospital — we were the heaviest twins ever born on record,” he says, seated in a noisy coffee bar here.

“I was 9 pounds, 3 ounces and my sister was 7 pounds, 5. My dad said, ‘When you were born, there was a crowd of about 20 people about to take on board this astonishing achievement.’ And he said, ‘So you kind of came out to an audience.’”

Ellis is shining in the medical arena once again. Only this time he’s playing a renegade doctor in USA’s edgy drama, “Rush,” airing Thursdays. His physician makes Dr. House look like Mother Theresa with his unholy alliances and affection for drugs.

Ellis may have been seeking attention since he was an infant, but he didn’t know it. The son of a music teacher and a pastor, it was music that dominated his childhood. “It’s just something that I relish really. It doesn’t make me nervous. It makes me comfortable. It excites me,” he says, his black leather jacket squeaking as he rests his elbow on the table.

At 4, he played the trumpet, changed to the French horn at 9 and continued all through high school to a high standard, he says.

But, at 17, the course of his life changed when he dropped a class he didn’t like. “I was planning on going to university and doing sports injury, recovery and rehabilitation. Sports was a good part of my life as well. . . I needed to do another subject to fill my criteria.

“My English teacher came up and said, ‘I run the theater studies group. I need some boys in the group because I’ve got 12 girls and no boys.’ I said, ‘Just stop right there — 12 girls and one boy?’” And I went to a couple of these classes and really, really enjoyed it.”

As it turned out it was more than the abundance of girls that attracted him. When his teacher presented an after-school play, Ellis won the lead and found he loved the process.

The mother of his friend was a former actress. She phoned Ellis the next day and told him he should pursue acting and offered to help him with auditions. She tutored him on how to prepare for the stringent drama school tryouts. To his surprise, he was accepted at the Royal Scottish Academy of Music and Drama in Glasgow.

“I remember the day I got a letter in the post saying I got a place at drama school and my mum and dad bringing it into my bedroom. And it was very unlike them. They came in together and they were quite excited, and they had this letter. It was a fat letter, not a slim, little rejection letter. And it had RSAMD on the front of it. They said, ‘You’ve got something! You’ve got something.’” And I opened it, and we all cried together. It was great.”

He landed an agent and a job in the second term of his final year of school. At first, everything went swimmingly. But, after two years, his career began to stall. “I’d been doing really well. I had my first dry period where I didn’t work for about six months.”

By then, his mother had changed jobs, landing a job in the medical field in Bristol. Once again, the medical world was beckoning and Ellis, 35, went to work for her as a receptionist.

“I was answering phones and meeting and greeting people. It was quite funny because everyone used to assume when I answered the phone that I was a doctor. They’re not used to a man answering the phone as the receptionist. People wouldn’t even let me get a word in edgeways. I’d say, ‘Hello.’ They’d say, ‘Oh, Doc, this is what’s happening to me,’ and they’d give me a whole list of ailments. ‘Could I just — I’m not a doctor.” But I look back on those moments in my life and think those are the things that make you better, certainly as an actor. Anything rooted in reality makes you a better actor.”

Finally, Ellis accumulated acclaim in England, especially for the sitcom, “Miranda.” But, like his compatriots, he longed to work in America and made countless trips to the U.S. during TV’s pilot seasons.

None of them came to fruition until “Rush.” “Three pages in I said, ‘I want to do this.’” They asked him to send an audition tape. “I had a funny feeling about it. I said, ‘I’m going to make this tape and I think I’m going to hear from somebody.’ And lo and behold, within 24 hours, I get a call from Jonathan Levine (executive producer) saying he loved my tape and he wanted me to do the job.”

The most difficult part of all that, he says, was the fracture of his marriage to actress Tamzin Outhwaite last year. “It was really hard,” he sighs. The father of three daughters, 9, 6 and 2, Ellis says, “It’s a bittersweet experience being over here. It’s happening because I love it and this is what I’ve always wanted to do. But I haven’t seen my kids for months, and that’s hard. They’re back in London. As soon as I finish, I’ll take a little vacation and have some ‘us’ time.”