'Orphan Black' Star Tatiana Maslany on Playing Multiple Clones

— -- Most actors play just one character at a time, but Tatiana Maslany has played nearly a dozen roles on the BBC America show "Orphan Black."

"There's a lot of 'How do you keep it straight in your mind? How do you differentiate these people? How do you become different people?'" Maslany, 30, told Peter Travers on ABC News' "Popcorn With Peter Travers."

The show follows clones who discover one another and search for their identity and for their origins. Maslany, who has played an array of clones, including a Ukrainian assassin, a suburban housewife, a drug-using cop and a transgender man, credits a team of people for helping her portray each character.

"The hair and makeup team are incredibly creatively collaborative with me. And we've created these characters together, you know, along with the writers and showrunners, but also I have a dialect coach who helps me get into the voices," Maslany said. "And then I have my acting double, who plays all the clones opposite me when I do. Her name's Kathryn Alexandre, and she's an amazing actor and does the most selfless, generous job on the planet, because she's never seen."

Though undertaking the complicated gig was initially daunting for her, Maslany said it's fun getting to play so many characters.

"I think, for me, it's the most natural thing an actor can do, is transform like this. I think that's we're born to do," she said. "At least the people I admire and the people I work with, we are thrilled to get to transform, and we're excited by that challenge."

Maslany, from Regina, Saskatchewan, also has her improvisation background to thank. Before she moved to Toronto to pursue an acting career, she worked in theater and television as a child. Improvisation helps her on "Orphan Black," she said, "in terms of character relationship and just story of in-the-moment building of a character ... We're really lucky. We really just are allowed to play [but] always within the scene."

She said that when she's not working on the show, she eagerly jumps into new roles.

"I definitely have to, like, shed the characters and the kinetic sort of nature of the show after I wrap," she said. "But the last two seasons, I went straight to a film right after, so I kind of dove into another world."

"That's a nice reset to be thrown into something different," she added.

Maslany recently starred in the film "The Other Half," in which she plays a woman with bipolar disorder opposite her real-life boyfriend, Tom Cullen, who played Lord Anthony Gillingham on "Downton Abbey."

"That's the story of two very kind of damaged people who come together because they see something in each other that is resonant and they kind of can see themselves inside each other," she said.

She added that Cullen is "a really interesting actor. He can kind of play so many different notes and so many different characters."

He has also her advice and support for "Orphan Black," Maslany said. "First season, I was in such a terrified panic. We'd have, like, three-hour phone calls where I'd just be like, 'I don't know what I'm doing. Help me' — you know, with the accent, with this, with that ... It's great to have someone like that to collaborate with."

And though she's been nominated for a best actress Emmy for the show, she said she doesn't think she'll ever be content with her performance in any role.

"The first episode of season one ... I'd been dreaming of this script for so long, and I pictured that opening sequence over and over in my head, then I got the part and got to stand on that train platform and do the scene, and it was, like, freezing cold, and I was looking at Kathryn, and there was something about being in someone else's shoes, like, mind-blowing," she said.

"I don't know that I'm satisfied with any part I've ever done, but there was a real satisfaction in just being there in that image that I'd dreamed about for so long."

Watch the full interview with Tatiana Maslany with Peter Travers on ABC News' "Popcorn With Peter Travers" above.