Kelly Rohrbach Admits Baywatch Co-Star Zac Efron's Abs Were Hard to Miss

That iconic red one-piece swimsuit may be the star of Baywatch, but you won’t be able to miss 27-year-old actress Kelly Rohrbach.

So what was it like to slip into that look? “When I first put the swimsuit on it was in a fitting and it was just a couple of pins and scraps of material. So it wasn’t until the first day of shooting in my trailer that I had that ‘aha! Oh my gosh, this is happening!’ moment. And by then, I was so nervous that it was my first day on set that I can’t even remember that moment of putting on the suit,” she tells InStyle in the video above.

Barely there outfits aside, Rohrbach proved to be a badass off camera, too, meeting with the writers and directors to tweak her character’s original lines. “Originally my character was written a little bit more standoffish to Jon Bass’s character Ronnie Greenbaum. When I met John, I instantly fell in love. He’s such a sweet person and such a great actor and so funny. So I thought how could anybody be cold to this guy? I sat down with the director and the writers and was like, let’s make it more interesting for the audience.” Mission accomplished.

Additionally, Rohrbach opens up about getting into tip-top beach-ready shape, and yes, all things Zac Efron. “Zac’s physical transformation was unlike anything I’ve ever seen. He was so ripped. He had muscles that I didn’t know we have,” she says. He worked really hard and was super disciplined. We’d all be like sneaking peanut M&M’s off craft services and he was like, ‘Guys, no! I can’t.’ So kudos to him ‘cause he made it happen.”

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Watch our full interview with the star above.