Sydney Sweeney has signed on to play real-life boxer Christy Martin in a movie directed by David Michod, best known for his Netflix films War Machine and The King. Martin is one of the famous female boxers of all time; she was the first woman to sign with famed promoter Don King and also became the first female boxer to features on the cover of Sports Illustrated. Sweeney told Deadline that she would be undergoing intense training in order to transform her body. The still-untitled film goes into production this fall.