Sydney Sweeney, known for her roles in "Euphoria" and "The White Lotus," is set to star as iconic boxer Christy Martin in an upcoming biopic. The currently untitled film, directed by David Michôd, will chronicle Martin's rise to fame in the 1990s, her personal struggles, and her tumultuous relationship with her husband and trainer, James Martin, who later attempted to murder her.

To accurately portray the groundbreaking boxer, Sweeney underwent a significant physical transformation. In an interview with W Magazine, she revealed that she gained over 30 pounds (approximately 14 kg) for the role. She embraced a rigorous training regimen that included weight training in the morning, kickboxing midday, and more weight training at night, all while adhering to a diet plan designed to help her gain weight.

Sweeney described the changes to her body as "crazy." She went from a size 23 to a size 27 in jeans, and noticed significant changes in her bust and glutes. However, she also expressed her enthusiasm for the transformation, stating that she "loved" the process and felt "crazy strong." Sweeney also mentioned on The One Show that she trained for two and a half to three months before filming, crediting a nutritionist for helping her put on the weight.

The film is not just about Martin's boxing career, but also delves into her personal life, including her struggles with substance abuse and her identity as a gay woman in a conservative environment. The film will portray Martin's early life in West Virginia, where she used boxing as a means to express herself and her rage, as well as her relationship with her husband/trainer.

Director David Michôd praised Sweeney's dedication and work ethic, stating that she "trained her butt off" for the part and brought a positive attitude to the set every day. He described the film as a "wild mix of inspiring underdog sports-world story and personal saga."

In addition to Sweeney, the film stars Ben Foster as James Martin, Katy O'Brian as Lisa Holewyne (Martin's boxing rival and later wife), and Jess Gabor as Sherry Lusk, Martin's high school girlfriend. Production wrapped in November 2024, with Sweeney calling it "one of the most emotional, transformative experiences" of her life.

While an official release date has not yet been announced, the film is highly anticipated. Sweeney's dedication to the role, combined with the compelling story of Christy Martin, promises to deliver a powerful and inspiring biopic.