Who's that girl? It's Zooey Deschanel!

But you may have not known it from the New Girl alum's latest selfie. After all, Zooey swapped her signature brunette locks for a wavy blonde 'do a series of selfies shared to Instagram May 30. One image showed the 43-year-old clad in a blue bodysuit, black puffer coat and gray sweatpants as she showed off her hair transformation, while she was pictured in another standing inside what appeared to be a makeup trailer.

In both snaps, Zooey had curtain bangs instead of her trademark blunt fringe, prompting her to write in the caption, "who's she?"

Indeed, her new look had many fans doing a double take, with Nicole Scherzinger writing in the comments section, "giving me Olivia Newton-John vibes!" 

Other celebs people thought she was channeling included Christina Applegate, Chelsea Handler and Farrah Fawcett.

"I legit did not recognize you," one commenter remarked, while another joked, "Everyday she proves why people would've not recognised Clark Kent was Superman."

So, what's the story behind Zooey's blonde look? The sky-high hairstyle is actually for the actress' upcoming appearance on the third season of the '80s-based Apple TV+ series Physical. Per Variety, Zooey will play Kelly, a former sitcom star who jumps into the burgeoning fitness business at the height of the decade's aerobics trend.

Keep reading to see her bodacious 'do, as well as other dramatic hair transformations.

The "Say So" singer showed off her dramatic hair transformation on Instagram, debuting bright purple hair and a spooky spider design on the back of her head.

The Kick-Ass actress debuted a fresh bob haircut, which she hasn't rocked in quite some time.

The American Idol judge revived her signature style of 2008 and revealed baby bangs in a June 20 Instagram.

The Vampire Diaries actress debuted fringe bangs for the Los Angeles premiere of her new film Out-Laws in June.

The "Vogue" singer debuted an edgy shag haircut on June 11.

The Dance Moms alum proved you can be blonde and brunette at the same time with her recent hair change.

The High School Musical alum has entered her French girl era, after showing off her new curtain bangs.

The New Girl alum ditched her trademark brown hair and blunt bangs for a sky-high blonde 'do for her upcoming appearance on the '80s-based Apple TV+ series Physical.

The "Over It" artist headed into summer with a shorter cut and new hair color, debuting her blonde bob to Instagram in May 2023.

The X-Men star kissed her shoulder-length hair goodbye and debuted a pixie cut on May 26.

While attending the Louis Vuitton cruise show in Italy on May 24, Emma debuted curtain bangs—a style she often rocked in the mid-2010s.

The Sweet Home Alabama actress debuted wispy fringe bangs in a stunning selfie. 

The Poosh founder went back to her brunette roots, debuting a new look. As she put it on Instagram, she's a "brunette4lyfe."

Amid her ongoing transformation journey, the Rob & Chyna alum debuted a short pixie cut with shaved sides.

On May 15, the pop star opted for a bold hair color, rocking jet-black hair.

Helen Mirren wowed at the 2023 Cannes Film Festival, as she debuted vibrant blue hair.

Playing Lily Bloom in the film adaptation of Colleen Hoover's It Ends With Us, the actress was seen with red hair while filming scenes in New York City on May 15, 2023.

The Star Wars actress debuted her newly shaved head on May 10, writing on Instagram, "Happy without hair!"

On April 24, the Tangled actress debuted a fresh cut and fringe bangs.

The "Flowers" singer unveiled a drastic hair change, going back to her brunette roots, at The Daily Front Row's Seventh Annual Fashion Los Angeles Awards.

The TikTok star debuted a drastic hair change at Coachella 2023, unveiling a blonde bob look.

Ava Phillippe, the daughter of Reese Witherspoon and Ryan Phillippe, debuted blunt bangs in an April 4 Instagram.

The Elvis star went bald for his role as Feyd-Rautha in Dune: Part Two.

The actress debuted a long bob on April 3 that's perfect for spring.

"@craphairclub hair is giving me so much joy still," the daughter of Nicole Kidman and Tom Cruise shared on Instagram March 29 along with a photo of her 'do. "Thank you."

The Pretty Woman star showed off her fringe bangs and fresh hair color on March 27.

The supermodel debuted a pixie haircut in a March 20 Instagram, while also sharing behind-the-scenes snapshots of her photoshoot with Pop magazine.

The star debuted a red hot new 'do in March 2023.

Kourtney debuted her biggest hair transformation in March 2023.

After reverting back from blonde to brunette, the SKIMS founder zhuzhed up her signature look with curtain bangs.

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