Sydney Sweeney is mopping the house floor with her nostalgic transformation.
After months of styling her short bob, the 28-year-old debuted Old Hollywood curls at the Dec. 2 screening of her latest film The Housemaid in New York.
At the event, Sydney walked the red carpet with her bouncy tresses on display. Still sporting her signature blonde, her new 1970s-inspired curls filled her hair slightly below her shoulders. However, her nods to the retro era didn’t end there. The Euphoria actor also wore a silver Miu Miu gown, complimenting the look with a white feather boa and diamond-studded earrings.
Meanwhile, her costar Amanda Seyfried, 40, paired her wavy side-part with a plunging pink Versace gown and silver jewelry.
As for Sydney, her latest hair ‘do is a dramatic pivot from her bob. In fact, she last turned heads with her short cut—which she debuted ahead of her role as professional boxer Christy Martin in the biopic Christy—at Variety’s 2025 Power of Women ceremony in October. There, she added a sharp flip to the ends of her bob, which paired well with her sheer Christian Cowan x Elias Matso dress.
And true to the event’s theme, the Anyone But You star detailed how her transformation into the boxer empowered her as an actor.
“I know what it feels like to be underestimated—to have people define you before you’ve had a chance to define yourself,” Sydney said during the ceremony at the time. “I know what it feels like to have to prove that you deserve to be here.”
She continued, “Christy reminds us all that strength doesn’t have to look loud sometimes, sometimes it’s just about getting back up again and again no matter who’s watching.”
Indeed, Sydney persevered through a few obstacles to ace the role, including adopting a new carb-loaded diet and workout routine.
“I came onboard to play Christy, and I had about three and a half months of training,” she explained to W magazine in June. “I started eating. I weight-trained in the morning for an hour, kickboxed midday for about two hours, and then weight-trained again at night for an hour.”
By the end of her 30-pound transformation, Sydney admitted she “didn’t fit in any of my clothes.”
“But it was amazing,” she clarified. “I was so strong, like crazy strong.”
Keep reading to see more stars who experimented with their hair this year…
Sami Sheen
The daughter of Charlie Sheen and Denise Richards shared her at-home hair dying journey, including its many missteps, on TikTok and raved about the results.
“I've been wanting to do this to my hair for years now," she said, "and I'm so happy that I finally did it.”
Carrie Underwood
Trading in her signature golden locks, the country music star wrote on Instagram in August 2025, "Well, the last time I saw my natural hair color, I was probably about 12 years old, but I thought it might be time to give it a second chance."
Jason Momoa
In July 2025, the actor shaved off his beard for the first time in six years to film Dune: Part Three, which required him to rock a clean shaven look to reprise his role of Duncan Idaho.
Kelly Clarkson
The American Idol winner debuted a shorter hairdo in a July 2025 The Voice promo, trading her signature blonde waves for a shorter, darker bob style.
Chris Pratt
The actor debuted a bearded look, which he sports on season two of The Terminal List, in June 2025.
Finn Wolfhard
The Stranger Things star changed up his trademark shaggy hairstyle in May 2025 by debuting a buzzcut at the 2025 Crunchyroll Anime Awards in Tokyo, Japan.
Sebastian Stan
The Marvel actor said goodbye to Bucky Barnes' signature long hair in April 2025, showing off a shaved head at the Los Angeles premiere of Thunderbolts*.
JoJo Siwa
In March 2025, the "Karma" singer debuted her rainbow mohawk at the GLAAD Media Awards.
Emily Ratajkowski
In a March 2025 TikTok video, the model called this 'do with shaggy bangs the "worst haircut of my life."
Gypsy Rose Blanchard
The Gypsy Rose: Life After Lockup star debuted a short bob in March 2025, more than two months after giving birth to her and fiancé Ken Urker's first child, daughter Aurora Urker.
Whitney Rose
The formerly blond Real Housewives of Salt Lake City star debuted a red bob on Watch What Happens Live in January 2025.
Hailey Bieber
The model debuted lighter locks in September 2024, a month after giving birth to her and Justin Bieber's first baby, son Jack Blues Bieber.
Lily Collins
The Emily in Paris star debuted her dramatic transformation at the world premiere of her new horror movie, MAXXXINE, in June 2024.
"Changing my hair always brings out different sides of my personality and I love playing around," Lily told Vogue. "This cut and color feels bolder and yet somehow lighter. And completely more me—right now."
Katie Holmes
While attending Chanel's Tribeca Film Festival Artists dinner in June 2024, Katie debuted a subtle, yet striking transformation of rich caramel balayage highlights that were blended throughout her brunette tresses.
Kylie Jenner
The Kardashians star debuted a platinum blonde look and a bob haircut after rocking waist-length strands for quite some time.
"Did someone say they missed king kylie," Kylie teased in the caption of her June 8 Instagram post, to which her sister Khloe Kardashian cheekily replied, "I did! I did!!!!!!"
Lisa Rinna
The former Bravo star debuted a platinum blonde look during 2024 Paris Fashion Week Haute Couture.
Priyanka Chopra
The Heads of State star debuted a drastic haircut—a shoulder-grazing bob—while attending a Bulgari event in Rome i May 2024.
Jessica Biel
In May 2024, the actress chopped her hair into a bob that many fans on social media said reminded them of one of the looks she sported as Mary Camden on the '90s series 7th Heaven.
Megan Fox
The Transformers actress returned to her dark brown tresses and debuted a sassy bob in May 2024, a month after she dyed her hair blue to enter what she dubbed her "Jedi era."
Dannielynn Birkhead
At age 17, the daughter of the late Anna Nicole Smith debuted a new lob hairstyle overnight during 2024 Kentucky Derby weekend, which she attended with dad Larry Birkhead.
Demi Lovato
The singer debuted a lighter, shorter 'do in April 2024.
Kelly Osbourne
The Fashion Police alum debuted a blonde bombshell hair transformation May 8.
Kim Kardashian
Back to blonde: Kim debuted a new platinum 'do in April 2024.
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.