The secret to Dolly Parton's success as a movie actor is simple, the legendary performer explains during a new interview on Tim McGraw's Beyond the Influence Radio: She's always made sure to only say yes to roles that she felt she could believably portray.

For example, in her first-ever starring role — in 1980's 9 to 5 — Parton knew going in that she and her character were going to have a lot in common.

"When I read that part for 9 to 5, you know, it was a girl from Texas, and she was so much like me anyway, so that was not that far-fetched," the singer points out, adding that she has felt connected to her characters even in movies like Steel Magnolias, where she played a beautician.

"If I hadn't made it in the music business, I would have been a beautician. So I understood that," Parton explains. "I've always done my own hair. I used to do my mama's hair and my sister's hair. So every part I take, I have to be able to do that.

"...Even The Best Little Whorehouse in Texas. Although I made a better whore than I did a secretary," Parton jokes. "But it was still parts of my personality that I could relate to: All that gaud, showing my boobs and all that. So I always take things that I think I can pull off."

No matter what role she takes on, one thing is clear: Parton has always approached her film career with the same careful consideration she uses when writing, selecting and releasing songs. Elsewhere in the interview, she reveals that on several occasions, she's turned down roles that she didn't think were right for her. She also made sure not to start acting too soon in her musical career, she adds.

"I had been asked a lot of times to be in the movies, and I didn't think I was ready quite yet," Parton recalls of those early days. "I also thought, 'Well, if the right thing came along, I might be willing to do it.' Because I was still building my music career at the time."

That "right thing" finally presented itself when she had the opportunity to not only act in 9 to 5, but also write and perform the film's theme song. Plus, Parton adds, actors Jane Fonda and Lily Tomlin had both already signed on to do the film.

"They were both so hot at the time, and I thought, 'Well, if there's any time to start, this would be now, because if it's a big hit then I can share in the glory of it. If it's a failure, I can blame it all on them and walk away free,'" the singer jokes.

"....It actually turned out to be a very fun and rewarding and successful project," Parton adds.

See Dolly Parton's Life and Career in Pictures

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