This powerful documentary profiles the life and work of Mother Antonia (Mary Clark) an American nun who chooses to live among the prisoners in La Mesa Penitentiary in Tijuana, Mexico. Referring to the inmates and the prison guards as “my sons” Mother Antonia demonstrates the love and mercy of Jesus, whom she often refers to as “the Prisoner.” After living a charmed life in Beverly Hills California, God called Mother Antonia to Tijuana to serve those rejected by the world. For decades she has served as an intermediary between inmates and guards, diffusing violence, ensuring humane conditions and meeting practical needs. Through interviews with prisoners, guards, wardens and others who know her well, we discover what motivates this tenacious nun who serves a life sentence, by choice.