Rachel McAdams' new look is totally giving Janis Ian.
That's right, the Mean Girls alum no longer resembles Regina George, as she kissed her blonde stye goodbye and debuted a dramatic dark hair color.
While attending the opening night of Broadway show An Enemy of the People, March 18, Rachel ruled the red carpet with her epic 'do. And to highlight her drastic change at the New York City event, she sported effortless waves and parted her hair in a deep side part.
She also matched her dark brunette transformation with a deep navy blue ensemble, wearing a long-sleeve turtleneck with a coordinating faux leather midiskirt. As for her accessories? She kept it simple, donning navy Mary Jane heels, dainty earrings and layers of bracelets.
Although Rachel's makeover was unexpected, she's pulled off this hairstyle before. In fact, she rocked nearly black locks in 2005 when she starred in The Family Stone, Wedding Crashers and Red Eye.
But the 45-year-old's recent change is just one of the ways she's experimented with her style. After all, she made armpit hair look sexy during her Bustle cover shoot last April.
"I love that juxtaposition of beauty, glam, fantasy, and then truth," she said in the interview. "With this shoot, I'm wearing latex underwear. But I've had two children. This is my body, and I think that's so important to reflect back out to the world."
Rachel—who shares a 6-year-old son and 3-year-old daughter with partner Jamie Linden—added, "It's OK to look your best and work at it and be healthy, but that's different for everyone."
The Notebook alum has been open about her body transformation after becoming a mother. While working on the 2023 film Are You There God? It's Me Margaret, she noted how life was imitating art.
"'Why don't we just try this without a bra?'" Rachel told Bustle, recalling what the costume designer telling her. "The great irony is Margaret just can't wait to get into a bra. But I'm playing a kind of wild child, hippie artist mom [who] doesn't wear a bra throughout the whole film."
And Rachel could relate to her character Barb's struggles.
"I was worried some days. 'Is this too much? Is this distracting?'" she shared. "I hated thinking about that. Why do I even care? But it's hard not to!"
Of course, Rachel isn't the only star to make a drastic style change. Keep reading to see which celebs have pushed the beauty boundaries.
Rihanna
The Fenty Beauty founder debuted a bright blonde hair transformation April 17 while celebrating her latest Fenty x Puma collection in London.
Delilah Belle Hamlin
The model debuted a bleach blonde pixie cut at the FRAME event April 4.
Megan Fox
The Jennifer's Body star traded in her bubblegum pink tresses for a baby blue bob, which she debuted April 2.
Zendaya
Less than a month afer chopping her hair into a long bob, Zendaya debuted a honey blonde transformation at the Challengers premiere March 26.
Elle Fanning
The Great star ushered in spring with a fresh cut, as she debuted a long bob March 25.
Rachel McAdams
The Mean Girls alum swapped out her signature blonde hair for a dark brunette transformation on March 18.
Bre Tiesi
The Selling Sunset star looked completely unrecognizable after debuting a dramatic blonde transformation March 16.
Kelly Osbourne
The Fashion Police alum ditched her signature purple hair after six years, tinting it an icy silver in March 2024.
Zendaya
The Dune actress debuted a shoulder-grazing bob at Essence's Black Women in Hollywood Awards March 7.
Sydney Sweeney
The Anyone But You star made a showstopping appearance at Miu Miu's fall/winter 2024-2025 show during Paris Fashion Week. For the March 5 event, she unveiled a dramatic long bob haircut.
Zoey Deutch
To prepare for her upcoming role as Jean Seberg, the 29-year-old debuted a bleached blonde pixie cut.
Anne Hathaway
The Princess Diaries alum unveiled fringe bangs at the 2024 Film Independent Spirit Awards.
Selena Gomez
The star debuted a bangin' new style at the premiere of her friend Nicola Peltz Beckham's film Lola in February 2024.
Jennifer Lopez
The "On the Floor" singer made a dramatic hair change, as she debuted a chin-grazing bob cut at Schiaparelli's haute couture spring/summer 2024 show on Jan. 22.
Gypsy Rose Blanchard
In January 2024, a month after her prison release, the now-influencer shared a pic of herself sporting a shorter 'do.
Kylie Jenner
Kylie Jenner traded in her dark locks for a pink 'do in January 2024.
Julianne Hough
In January 2024, the Dancing With the Stars personality shared a video of herself cutting her own hair. "Out with the old energy," she wrote, "and in with the new."
Kate Beckinsale
The Underworld actress took the plunge and went full blonde, while also debuting a short bob haircut.
Riley Keough
The Daisy Jones & The Six actress debuted jet-black hair on Nov. 2.
Eva Longoria
The Flamin' Hot director recently showcased her dramatic transformation, debuting a choppy, layered bob on Nov. 9.
Alix Earle
The TikToker debuted a fresh haircut, revealing a long bob.
Miley Cyrus
After rocking platinum blonde tresses for years, Miley officially returned to her brunette roots to model Gucci's new collection.
Kate Middleton
The royal recently showed off her new curtain bangs during a public appearance on Sept. 27.
The actress recently debuted a bright red hair color and equally bold blunt bob haircut.
Cara Delevingne
The supermodel debuted a punk-rock hairstyle at Vogue's World Show during London Fashion Week on Sept. 14
Brittany Snow
The Pitch Perfect star made a drastic hair change, going from dark brunette tresses to a bright blonde look.
The Scream actress debuted a bubblegum pink style in August 2023.
The son of David Beckham and Victoria Beckham got his head shaved by Selena Gomez's little sister, Gracie Teefey, in August 2023.
The Can't Hardly Wait actress showed off her drastic hair change, debuting dark red hair and a blunt bob haircut.
The Second Act star unveiled bright blonde highlights in a new selfie.