Bo Derek plays Tara Reid's mom in Sharknado 3: Hell No!, and ET talked to the sex symbol about aging in Hollywood and her famous boyfriend, John Corbett.

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At 58, Bo is finding peace with some of the aspects of aging, but then there are still others that she could do without.

"I feel I'm aging like other people," Bo told ET. "I feel it's not fair. I don't mind the years. I just mind the look. I miss my skin."

It was 36 years ago that Bo became an instant sex symbol when she ran down the beach in the 1979 film 10. Today, Bo has found that roles don't come easy for women in Hollywood after 50.

"I don't play the parts I used to play, obviously," Bo said. "I've been a producer. I wouldn't cast me in a lot anymore. At the same time, I'm guilty too. I like to look at younger faces on the screen, and most of our stories are told by younger people because they're the ones that would make a difference in a plot or storyline most of the time."

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In the decades since 10, Bo has branched out to behind-the-camera gigs. She recently shot her co-stars Tara and Ian Ziering for the cover of TV Guide, which hits stands Thursday.

"Ian's very opinionated," Bo noted of the former Beverly Hills, 90210 star. "I remember one idea I had. I showed him an example of what I wanted to do and he looked at it and said, 'Ok, for you I'll do it.'"

Ian, 51, is only a few years younger than Bo's Sex and the City star boyfriend John Corbett, whom she's been with for 13 years. While they're happy together, Bo says that she's in no rush to put a ring on her finger.

"He's funny. He makes me laugh all the time," Bo said. "We talk about [marriage] sometimes but we don't have children and we're not young, so there isn't that pressure or need to get married."

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The Sharknado franchise seems to carry the same no-pressure spirit, throwing all caution to the wind.

"It's just so campy and fun," Bo gushed. "It's the popcorn, the laughing, the screaming, the having a good time -- it's a very social experience."

Sharknado 3 debuts Wednesday, July 22 at 9/8c on Syfy.