She may have played sweet and innocent Sandra Dee on Grease Live! but Julianne Hough's shag haircut is more rock 'n' roll than girl-next-door. The multi-talented star debuted her shaggy bob hairstyle on Instagram (while jamming to Selena Gomez in the car) and received a ton of positive comments from fans. Her stylist Riawna Capri also shared a montage of photos to show the varying lengths and layers of Hough's new hairstyle, which she described as a "modern day shag."

"Loving this little change so much!" Capri said. "When [you're] growing out your hair, make sure to have fun in the process!!! We do!!!" The shag haircut saw a resurgence in popularity a few months ago, thanks to fashion "It" girls like Alexa Chung and Chloe Sevigny sporting the iconic 'do. But, this style has definitely been around for years and has been worn by various celebrities including Joan Jett, Farrah Fawcett, and Jennifer Aniston — whose Friends character popularized a version of the shag into "The Rachel" haircut.

Hough showed off her new 'do on Instagram... while singing along "Hands to Myself" of course. She's clearly loving this new look and putting her own spin on this classic chopped hairstyle.

So chic!

It's so good from every angle.

Even though her shag is a new look for Hough, she's always had fun styling her hair for the red carpet. While promoting the Fox hit Grease Live! a few months ago, she rocked these gorgeous side-swept bangs.

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Hough's top knot at the People's Choice Awards is oh-so-chic.

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She gave a nod to hair icon Farrah Fawcett with this feathered hairstyle at a party.

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Hough went for an ultra sleek, '80s glam look at the American Music Awards.

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I don't know about you, but I'm hopelessly devoted to Julianne Hough and her new shag haircut.

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