Based on Kathryn Hulme’s novel and directed by Fred Zinneman, the daughter of a famous doctor becomes a nun and works with a free-thinking surgeon in the Belgian Congo.
Gabrielle van der Mal (Audrey Hepburn) takes off an engagement ring and puts it with a note to send it to Jean. She goes downstairs where her father Dr. Van der Mal (Dean Jagger) is waiting for her to leave. He waits outside while she says goodbye to her sister Louise. Outside she kisses her younger brother Pierre goodbye. She wishes they were as happy as she is and gets in a car with her father.
Gabrielle and her father walk to a church, and he questions whether she will be able to obey. He tells her she can come back home without failing. They go in the church. Sister William (Patricia Colline) is there. A man who had an operation by Dr. Van der Mal introduces his daughter Simone (Patricia Bosworth) to them. Sister Margharita (Mildred Dunnock) comes up to them also and says who she is. She welcomes Gabrielle and tells her father that his daughter will be a great nurse. He tells Gabrielle that Margharita is a “living rule” because she is a “perfect nun.” Gabrielle has her father hand over her dowry to a nun. A bell rings, and the postulants say goodbye to their families. Gabrielle wants her father to be proud of him and says she is happy. He embraces her and leaves. More than a dozen young women are led away by the nuns.
In another room they take off their coats and put on black veils. Gabrielle is given number 1072. They are admitted with the oldest first, and that determines who has been in the order longer. Gabrielle learns from Sister William that for the first six months she can not speak to them except in matters of work. Sister Margharita says that one of their first disciplines is silence. She unlocks the door and leads them to the chapel for evening prayers. Sister William locks the door.
In the chapel they kneel and pray. A nun lays on the floor before the altar and then gets in one of the long lines of nuns. They chant a prayer.
At five in the morning a nun wakes them up to pray. In a classroom Margharita lectures the postulants on inner silence, explaining the appropriate behaviors. She teaches them sign language for common messages. They never touch another sister but can pull on a garment to get attention. They never hurry and walk close to the walls. Gabrielle comes running in late and has to go back and walk slowly.
They enter the sanctuary where dozens of nuns are lined up. The postulants prostrate themselves in front of Rev. Mother Emmanuel (Edith Evans) who has them rise and explains to them how difficult it is to be a nun because it is against nature. Sacrifices can be borne only with love. They will be given exercises and tests in humility to prepare them. If they question them, they do not belong there. The perfect nun is always obedient.
The postulants learn to obey the bells that call them to duties. Gabrielle works as a nurse taking care of a patient in a hospitable.
They are given notebooks to record every little error they make. Their voices are heard accusing themselves of various offenses.
Gabrielle comes into the office of Emmanuel who says it is too soon to assign her as a nurse as her father wishes. Gabrielle agrees, and Emmanuel says she has to mature in the religious life.
Sister Margharita lectures them about detachment and says they must give up all possessions from their former life they may still have there.
The next day the postulants are dressed in white as they enter the sanctuary observed by their relatives behind bars. A prelate asks them what they are asking, and they chant together. They renounce all the pleasures of this world. He asks if they do this freely, and each one answers yes. All the nuns kneel, and the priest prays. The nuns chant as Emmanuel gives each postulant a folded white cloth, the habit of humility. They file out to another room where a nun cuts off Gabrielle’s hair and puts on the white cap and veil. Now the postulants are dressed as the other nuns and return to the sanctuary. The other nuns give them candles. They are given new names. Gabrielle is to be called “Sister Luke.”
In the hospital the patients summon Luke with a bell and applaud her as a beautiful nun. Gabrielle leaves the room and talks with another new nun, agreeing they must record that they talked alone.
For the next year they will not leave the mother house. Now they must confess their faults before the others and do penance for them. Sisters are to proclaim the faults others have not confessed. The proclaimer says what they saw as the one observed prostrates on the floor. Emmanuel states the penance they must perform. Gabrielle is called out for seeking the company of another nun and has to kiss Emmanuel’s feet.
They scrub a floor on their knees. Gabrielle prays in the sanctuary, saying she is failing in humility because of her pride. In the hall Simone tells Gabrielle that she can speak to her because she is leaving and not taking her vows. Gabrielle asks why. Simone says she would be cheating God and herself if she went on. Gabrielle says she is the weakest. Simone apologizes for causing her another penance and asks her to pray for her.
Gabrielle reads from a paper, promising to obey the holy rule for three years, and she signs the document. The priest blesses her. Emmanuel gives her a black veil.
Emmanuel tells Gabrielle she must use a whip on her back gently as a symbol of penance. She is to go to a school in Antwerp.
Gabrielle is using a microscope, and Dr. Goovaerts (Lionel Jeffries) says she is her father’s daughter. Dr. Goovaerts reprimands Sister Pauline who served in Africa and could not identify leprosy. He tells them about the Congo and asks Luke to help the others. Luke identifies something that is very similar to leprosy and explains the difference.
Nuns get off a streetcar and go into a building. Luke knocks and goes in and kneels before the Reverend Mother Marcella. She confesses she has unfriendly feelings toward Pauline. Marcella says Pauline feels that Luke is full of pride. Pauline is afraid of not being able to return to the Congo. Marcella asks Luke to fail her examination to show her humility. Luke says she would if the mother house knew why she failed. Marcella says that would not be a real humiliation. Luke asks how she knows that God wants that from her. Marcella tells her to pray.
Dr. Goovaerts and two other men question Luke in an oral exam, and after a pause she gives the answer. She answers each question as best she can.
Marcella tells Luke, Pauline, and two others that they all passed the exam. The others are assigned to the Congo, but Luke is assigned to a mental sanatorium near Brussels. Marcella explains that Luke must learn to accept what happens to her and says she was fourth in a class of eighty.
Luke is told that she is to accept as normal what the insane women do. A nun shows her the dangerous patients in cells. One woman believes she is the Archangel Gabriel (Colleen Dewhurst), and she is very dangerous. Luke is taken into a room where women are enclosed in tubs. Luke is assigned to be Sister Marie’s assistant there.
While walking along a street, Mother Christophe (Beatrice Straight) says she read Luke’s letter from her father who asked why she has to spend time there after studying tropical medicine. Luke apologizes for him. Nuns in the colonies must have perfected the religious life.
Luke is working in the room with the cells, and Archangel Gabriel asks her for a drink of water. Luke fills a metal cup and unlocks the door. The mad woman pulls her into the cell, and they wrestle. She won’t let Luke go out and grabs her. Luke gets free and escapes, closing the door. She locks the door and rings the alarm. Two nurses run in, and she tells them it is Gabriel. A nun comes in, and Luke says she is always disobedient.
Luke accuses herself of various imperfections to Mother Christophe, who says the suggestion to fail the exam was wrong. She advises her to bend before she breaks. Luke says she wants to be a good nun. She hopes for a resting place, but Christophe says there is none.
Sister Luke reads a paper, taking her final vows until death. The priest declares her a bride of Jesus Christ. She asks Emmanuel to pray for her.
Luke is leaving on a ship, and her father waves to her from the dock. On the voyage to Africa she prays she can do good.
From a train she sees villages. She hears a band playing in welcome. Most are Africans with a few European officers and nuns. Luke is with Sister Augustine and meets the African servant Kalulu and then Mother Mathilde (Peggy Ashcroft) and Sister Aurelie (Dorothy Alison). The four nuns board a small boat to cross the Congo River. Kalulu says the drums welcome them.
Later at the convent a nun tells Luke that the drums said she is young enough to bear children. Mathilde shows her around to meet Africans. Luke has studied their language and hopes to learn more. Father André (Stephen Murray) shakes hands with her and says they need her. Mathilde explains that some women come there to deliver their babies. They hear drums and see children running around. The students speak in unison to them and repeat their lesson.
Women with babies are lined up to be treated by a nun who shows them how to wash their babies. Luke learns that she is to be stationed at the hospital with the Europeans, and she is disappointed. Mathilde says a nun got tuberculosis and had to leave. Luke will have two jobs there working for the surgeon Dr. Fortunati. Mathilde takes Luke to the hospital and introduces her to Illunga (Errol John) who will be her deputy. Mathilde says Dr. Fortunati is a genius and a devil and works too hard. She warns him about him because he is a bachelor and an unbeliever. Mathilde leaves her there.
Dr. Fortunati (Peter Finch) comes in and meets Luke. He says she must get up at four for his surgery at five and take mass at the door. She says she will have to ask the Reverend mother, and he says he is in charge of the government hospital. She tells him who her father is, and he catches her in a display of pride and walks off.
During surgery Illunga and Luke assist Fortunati who tells her not to faint. She asks him not to eat garlic before an operation, and he promises. Father André gives communion at the door to Luke quickly, and she returns.
Luke looks after patients. Mathilde hears a European patient praising Luke. Mathilde asks Luke about her innovations reported by the drums. Mathilde says she should have told her what she was doing.
An African asks Luke about her husband and does not understand how all the nuns could have the same husband. She says her husband is in heaven, and he says he is sorry.
Fortunati tells Luke he is going fishing for the weekend and advises her to get some rest too. He asks if she fishes, but she does not answer. He leaves. She hears a bell and opens her prayer book. A nun comes in and tells Luke that Father André has had an accident and needs help. Luke asks her to catch Dr. Fortunati. André is carried in, and she tells others to call a surgeon. Luke says the leg is shattered and needs to be amputated. The nuns could not find a doctor, and Luke says they will try to save the leg.
Later Fortunati tells Luke she saved the father and his leg. He is sending her with Mathilde to see Father Vermeuhlen, the white saint of the leper colony, to make sure he does not have leprosy. He says she is tense because of an inner struggle. She says she should proclaim her fault every time he speaks like that. He apologizes and goes out.
Africans paddle a canoe with Mathilde and Luke aboard. Father Vermeuhlen (Niall MacGinnis) meets them at a dock. Mathilde explains that he is doing penance by treating lepers for the rest of his life. They observe many lepers. Vermeuhlen say they would be left to die in their villages. She observes that he has leprosy too, and he says it was just a matter of time. Luke and Mathilde leave in the canoe.
Luke on the phone asks permission to miss vespers while she is working. She does many tasks and breaks a bottle. She cries, and Fortunati comes in. He says it is after midnight and asks what they are going to do with her. He asks who listens to her troubles. He orders her to go to bed.
Luke looks in a microscope and tells Fortunati that she has tuberculosis. She made a test and will have to go back to Europe. He says he cannot lose her. He demands to examine it. She loosens her clothes, and he uses a stethoscope on her back as she breathes and coughs. He says it is a small lesion, and they may have found it in time. He recommends the gold treatment. She must tell Mathilde, and he says they will send her home. She cries and says she knows that. He knows she will not be able to stand the convent because she is not in the mold. She is a worldly nun and has her own ideas. He says that is her illness. She wants to stay, and he says he will tell Mathilde so that she won’t be sent home. He advises her to keep it secret.
Luke is living in a tree-house. She is in bed, and a nun brings her a monkey. A bell rings, and the nun leaves. Luke reads her prayer book.
Fortunati prepares an egg with lemon for Luke to drink. He says drums passed the word, and food will be brought for her. He says she must drink wine every night. He gets her to laugh and tells her to rest.
A knock wakes Luke, and Mathilde brings her the wine and sandwich. Luke says she has nothing to confess, but Mathilde says she talked during the grand silence.
Fortunati is glad that she is getting well. He says it will not be easy for her to return to her community, and he will miss having her there.
Sister Aurelie tries to get Illunga interested in going to the chapel, but he declines. Later an African tells Aurelie he needs his hand treated. He enters the hospital, and she tells him to go outside. He hits her with a club, and she walks toward him. He hits her twice more and is captured by three Africans. Illunga pulls off a fetish from his neck. The nuns find that Aurelie is dead. Luke asks Illunga to take papers to Sister Raphael. He asks her why she is not angry with them. She asks him why he did it. Illunga explains that the witch doctor said it would free him of his dead wife. Illunga says they would kill the man, but she says they forgive. She asks him to invite them to chapel on Christmas Eve.
Some Africans are in the chapel for the service. The nuns sing a Christmas carol, and Luke sees Illunga.
Fortunati finishes a surgery and instructs Luke about a trip to Belgium on a case. Mathilde tells Luke she is the only one qualified. Mathilde says Luke will have a replacement.
Fortunati tells Luke he will give her what she needs. They know war is coming to Europe. He says he had to send her. He is not sure of her religious faith, and she refuses to discuss it.
Luke walks outside and is determined to come back.
She says goodbye to Mathilde and boards a train. Illunga shows her the flowers in her compartment and gets off the train. Many people wave goodbye to her.
On a rainy day Luke returns to the convent and notices Sister William. Mother Emmanuel welcomes her with a kiss and asks about her health. She says Luke is very respected. Emmanuel says she will be a good example and can stay there. Luke asks if she can help at the hospital, but Emmanuel says no; she needs a few months for her spiritual life.
Her father visits Luke. He does not believe that she had tuberculosis because one does not survive that in the tropics. She says her doctor was exceptional. Her brother and her sister’s husband are in the army. He asks how she really is. She says she is fine, but he is lonely for her. He says Jean never married.
Luke rests and remembers things Fortunati and Mathilde said to her. She prays in the sanctuary for detachment from her memories. She still hears Fortunati’s voice.
In the garden Emmanuel urges Luke to go on a retreat. Emmanuel cannot send her to the Congo because of the talk of war. She assigns her to a hospital there.
At a meal the nuns hear an announcement that Germany has begun a war.
Luke assists during surgery, and they hear explosions.
The nuns learn that Germans have occupied all of Belgium and part of France. King Leopold signed a surrender, and the sisters are urged not to take sides against the order of the occupation.
At the hospital German soldiers stand guard. Luke answers a phone and summons the nurse Lisa (Diana Lambert) to speak to a priest. Lisa asks permission to go into town to visit her sick uncle. Luke says not to use that excuse again and asks why she is going. Lisa says they are hiding their soldiers, and she has to go. Luke asks if she can help too. Luke prays for forgiveness because she cannot obey.
The nun gives Luke a letter. She reads the letter from her brother Pierre which informs her that their father was killed. She prays and tries to forgive.
Luke confesses to a priest that she is a hypocrite because her heart is full of hate. She did not regret it when a German war nurse died. She says she cannot obey, and he tells her not to be so hard on herself. She asks him to notify the cardinal that she is no longer a nun. He asks her to go on, and she agrees. He asks her to speak to Emmanuel, but she refuses. She insists that he put her case, or she will leave without permission.
Emmanuel and Luke sit down to talk. Luke says her struggle has ended. Emmanuel says the nuns respect her. Luke says she has been struggling all these years. She can no longer practice obedience. She says her conscience asks which has priority, and she breaks the rules. She refuses to leave her work when a bell rings. Emmanuel says she is a nun more than a nurse. She asks her to make one more attempt for her. Luke says she tried. Emmanuel says she will pray for her and leaves.
Luke asks Lisa if she wants to become a nun. Luke asks if she is doing so out of admiration. Luke tells her she is going out. Lisa asks what happens and gives her an address. The underground needs nurses.
An archbishop asks Luke if she is doing it of her free will. Mother Didyma (Barbara O’Neil) asks if she is sure. Luke signs three papers, and Didyma asks if she has somewhere to go, Luke says she does. Gabrielle signs both her names. Didyma requests her keys and sends her to the porteress with the dowry she must accept. Gabrielle kneels, and Didyma goes out.
Gabrielle goes into a room and finds her clothes and a small suitcase. She takes off her veil and cap first. Finally she removes a gold ring and leaves it there. She presses a button, and a door opens to the outside. She walks away slowly with the suitcase.
This drama explores the challenges of practicing a life of religious discipline in the modern world for a person who believes she has important work she can do beyond that religious life.