Sydney Sweeney Transforms to Play Professional Boxer with Muscled Arms and Brown Hair: ‘Cat’s Out of the Bag’

Sydney Sweeney has undergone quite the transformation for her latest role.

On Wednesday, Oct. 16, Sweeney, 27, shared two photos of herself to Instagram from the set of an upcoming biopic in which she stars as former professional boxer Christy Martin. “well the cats out of the bag thanks to some paps in bushes so here’s a little bts from my film im working on right now,” Sweeney wrote in a caption, referencing paparazzi photos of her on set that were published in recent days. 

The pictures show Sweeney wearing dark brown hair in bangs instead of her typical blonde locks and flexing her toned arm muscles in order to play Martin, 56, who competed in the 1990s and 2000s.

“Over the past few months, i’ve been immersed in training to bring to life the story of an incredible woman—a true champion who fought battles both inside and outside the ring,” Sweeney added in the caption to her post. “her journey is a testament to resilience, strength, and hope, and I’m honored to step into her shoes to share her powerful story with you all. more to come soon :)”

Sweeney confirmed in a May 8 Instagram post that she would star as Martin in a biopic directed by David Michôd (The King.) At the time, Sweeney also told Deadline that she took up kickboxing between ages 12 and 19 and that she was “itching to get back in the ring, train and transform my body” for the movie.

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“Christy’s story isn’t a light one, it’s physically and emotionally demanding, there’s a lot of weight to carry. But I love challenging myself,” she told the outlet, stating that Martin “not only legitimized female boxing, she overcame gender stereotypes and fought through emotional, physical and financial abuse.”

Martin was known as “The Coal Miner’s Daughter” during her boxing career, in reference to her father’s profession, according to her official website. She was the first woman boxer to ever sign with the sport’s famous promoter Don King, held a 49-10-3 record as a professional boxer and was inducted into the International Boxing Hall of Fame in 2020.

“Christy’s story shines a light on her incredible rise to the top while showing the struggles of fame behind the curtains,” Sweeney told Deadline of the movie in May. “I feel compelled to tell a story about a woman who faced so much adversity and didn’t allow it to defeat her.”

Sweeney’s upcoming movie does not yet have a title or release date. The Anyone But You star is coming off a year in which she appeared in three movies, including Madame Web, Immaculate and Ron Howard’s latest movie Eden, which recently premiered at the Toronto International Film Festival.