Sydney Sweeney is entering a new era.

The 28-year-old actress debuted her latest transformation – a bleach blonde bob with soft waves – at the "Christy" premiere that took place during the annual AFI Fest in Los Angeles on Oct. 25.

Hair stylist Glen Oropeza revealed in an Instagram post that the look was the result of a "weeklong transformation." In the video, Sweeney goes from dirty blonde, with Oropeza methodically snipping the ends of her chin-length hair, to an icy, bright blonde.

Hair colorist Jacob Schwartz described Sweeney's new color in an Instagram post as "bleached suede blonde."

"Sydney was looking for a change and wanted to have a big hair moment for the red carpet to support her new movie, 'Christy,'" Schwartz told Vogue. "It felt like the perfect time to do something bold."

"'Christy' has a lot of underlying tones of resilience, transformation, and power. Sydney herself transformed herself for this role, and I wanted to morph her into this updated version of herself in real life," Oropeza told Vogue. "Something new and fresh to close out the rest of the year."

He also noted that this was the shortest Sweeney's hair has been since she stepped into the Hollywood spotlight.

In portraying pro boxer Christy Martin, the "Euphoria" star became nearly unrecognizable in the new David Michôd-directed biopic. She wore brown contact lenses, sported a shaggy brunette hairdo, and pushed her body to the limits by putting on 30 pounds of muscle.

To achieve the physical transformation, which had her wearing jeans four sizes bigger than usual, Sweeney trained three times per day for three and a half months. She also ate "a lot of Chick-fil-A, a lot, a lot of Smucker's, a lot of milkshakes, a lot of protein shakes," she said during a Q&A at the Toronto International Film Festival in September.

This article originally appeared on USA TODAY: Sydney Sweeney reveals shocking hair transformation at 'Christy' premiere

Reporting by KiMi Robinson, USA TODAY / USA TODAY

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