Two teenagers are brutally murdered by Joseph and Anthony de Rocher.
In a poor New Orleans school, Sister Helen and Sister Rose teach a hymn to a group of children. Helen is distracted as she thinks about her plan to visit Angola State Penitentiary where her new pen pal, a death row inmate named Joseph de Rocher, has asked her to visit. Against Rose’s advice, Helen makes the long drive to Angola and ponders the momentous step she is taking. A motor cop stops her for speeding, but lets her off with a warning, asking her to pray for his sick mother. As she resumes her journey, she prays for guidance.
When she arrives, Helen is greeted by the prison chaplain, Father Grenville. On the way to his office, they see inmates engaged in a rough game of basketball. Helen and Grenville then have a tense meeting in which the chaplain angrily warns her that she is wasting her time, and that Joseph is beyond anyone’s help. The prison warden arrives and tells her that Joe is likely to ask her to become his spiritual advisor to help prepare him for his execution. As she walks to the death row section of the prison, Helen is taunted by the inmates,
Joe and Helen have an awkward first meeting. Hiding his fear with bravado, he tests her tolerance by recalling the pleasures he has known with women. Helen calls his bluff and Joe admits his fear. He requests that she be his spiritual advisor and both acknowledge they “can’t do it alone.” Joe asks her to accompany his mother to the Pardon Board hearing and Helen agrees.
In a courtroom setting, the frightened Mrs. de Rocher does her best to plead for her son’s life: she is a small woman in the face of enormous hostility. During her testimony, Owen Hart, the father of the murdered teenage girl, explodes with anger and recounts the grisly details of his daughter’s murder. In anguish, Joseph’s mother responds that another killing cannot undo what has been done.
After the hearing, Joseph’s family and the murder victims’ families wait for a verdict outside the courtroom. Helen introduces herself to the parents and they express their grief at never seeing their children again. News arrives that the appeal has been turned down: Joseph will be executed.
Back in the visiting room, Helen tells Joe that an appeal has been made to the governor. Angered by his selfishness, she urges him to acknowledge his guilt and seek forgiveness, but he sees no hope and blames his brother for the murders. The warden appears suddenly and insists that she leave. Helen has had no time to eat and becomes faint from hunger, stress, and exhaustion. As she looks for change at a vending machine, a jumble of conflicting voices clutter her mind. The warden tells her that the governor has turned down the appeal: “Joseph de Rocher is a dead man.” The voices in her head grow louder and Helen faints.
Joseph is counting pushups when the warden comes to tell him that his execution date has been set: August 4, midnight. Alone, Joe voices feelings about his impending death, Sister Helen, and his murder victims.
Helen awakens from a nightmare about Joe and the murdered teenagers. Rose comforts her and helps her admit that she still has to find the strength to forgive Joe herself, just as mothers forgive their children’s failings.
On the night of Joe’s execution, Helen tells him about seeing Elvis Presley in person when she was a girl. Somehow, their shared love of Elvis opens a door between them and they are able to laugh as friends. She once more urges Joe to admit his guilt and find forgiveness. The warden announces that Joe’s family has come to see him for the last time.
Joe has a tearful farewell with his mother and two younger brothers. Joe begs his mother to forgive him, but she says she believes what he has always told her: that he is innocent and there is nothing to forgive. Mrs. de Rocher seeks comfort in her recollections of Joe’s innocent childhood. When Joe is led away, his mother falls apart, consoled by Helen with assurances that there is good in her son and that God’s love is not denied him. Left alone, Helen panics for a moment as she contemplates the harrowing task she faces that night.
The parents of the murder victims have arrived to witness the execution. They upbraid Helen for siding with the murderer, rejecting her words of consolation. Only Owen Hart voices doubts about the value of the execution. Helen offers him friendship and promises to visit him.
After the guards prepare Joseph for execution, Helen is alone with him one last time. In the few moments remaining, Helen begs him to tell the truth. She reveals that she has visited the crime scene and asks him to relive that night. Reluctantly, Joseph tells her the whole story and, breaking down in sobs, admits his guilt. Helen assures him of forgiveness: not only hers, but God’s as well. She tells him she will be the face of love for him when he dies.
The warden calls out, “Dead man walking.” As he escorts Joseph to the execution chamber, Father Grenville intones the Lord’s Prayer, echoed by the voices of inmates, nuns, guards, and parents. Helen remains close to Joe, reading to him from the Bible. She is allowed this one time to touch him, and she puts her hand reassuringly on his back. When they reach the chamber, she is barred from going any further. Joseph and Helen exchange an emotional good-bye. She reminds him to look for her as she takes her place with the others in the viewing room. After being strapped to the execution table, Joseph asks the parents’ forgiveness. In silence, with only his heartbeat audible, the lethal injection is administered. In his final moment, Joseph says to Sister Helen: “I love you.” After his death, the witnesses leave and Helen is alone with Joseph. One last time, she sings her comforting hymn: “He will gather us around.”
– synopsis courtesy of Jake Heggie