Haunted by a tragic past, ex-Marine Tommy Conlon returns home for the first time in fourteen years to enlist the help of his father to train for SPARTA, the biggest winner-takes-all event in mixed martial arts history. A former wrestling prodigy, Tommy blazes a path toward the championship while his brother, Brendan, an exfighter-turned teacher, returns to the ring in a desperate bid to save his family from financial ruin. But when Brendan's unlikely, underdog rise sets him on a collision course with the unstoppable Tommy, the two brothers must finally confront each other and the forces that pulled them apart.