The narrative begins in West Virginia in 1989 as Christy Salters demonstrates fierce power in Toughman contests. Facing rejection from her conservative mother Joyce over her relationship with girlfriend Rosie, Christy aligns with veteran trainer Jim Martin to escape. Jim gains financial and emotional control over her as she climbs the ranks. When Don King puts Christy on Mike Tyson undercards, Jim solidifies his dominance by marrying her, which provides Christy a heterosexual cover.
Over the subsequent decade, Christy endures chronic abuse, coercive control, and substance issues. Her trajectory shifts upon fighting Lisa Holewyne; their bond inspires Christy to embrace her identity and leave Jim. In November 2010, after Christy announces her departure, Jim brutally stabs and shoots her in their Florida home. Believing she is dead, he leaves, allowing Christy to summon the willpower to drag herself out, flag down a car, and apologize to the driver for getting blood on the seat.
Christy survives emergency surgery and testifies against Jim, who receives a prison sentence. The film concludes with Christy embracing her identity, entering a partnership with Lisa Holewyne, and becoming a survivor advocate.