Christy Martin was a trailblazing female boxer who revolutionised the sport in the 1990s. The fighter from West Virginia known as 'the Coal Miner's Daughter' was the first female boxer signed up by legendary impresario Don King and was undefeated in the ring for a decade. But in her personal life, she was fighting for survival, hiding her sexuality and trapped in a marriage that turned violent. Australian director David Michod and writer Mirrah Foulkes have turned this life into a Hollywood film