''There are not so many good Hollywood pictures about Christian spirituality, and some of them are just silly magic shows. But this picture, directed by Fred Zinnemann and adapted by the playwright Robert Anderson from a best-selling book by Kathryn C. Hulme, is a major exception. The story is based on the life of Hulme's lifetime companion Marie Louise Habets, a Belgian woman who took her vows in the early '30s. Habets' father was a prominent doctor, she'd had extensive medical training, and she bristled at the absolute obedience demanded by her order. She was pained to leave the Congo, where she felt that her expertise was most useful. When her father was killed by the Nazis she made the painful decision to leave her vocation in order to join the resistance. The power of this film lies in the fact that its central conflict is genuinely spiritual. We are taken through every stage of the rigorous demands of training for sisterhood, and the storytelling is clear, handsome, and carefully detailed-- you come away remembering the sounds of the morning bells, the texture of wooden doorways, the footsteps, the different parts of the nun's habits. And as the film proceeds, the spiritual conflict becomes increasingly acute. As a nun, do you owe your obedience to your order or to your conscience? And, is your conscience where your spiritual awareness truly lives, or is it within the observance of religious rituals? Audrey Hepburn plays Gabrielle, or Sister Luke; she is as delicately beautiful here as in any of her romantic pictures, and she gives a compellingly intelligent performance: you can feel her character trying to correct her own inner impulses as she moves from one trial to the next. The Nun's Story, like all of Zinnemann's films, is made with an exquisite sense of craft that is a thing of beauty in and of itself. A moving and, in the end, oddly haunting experience.'' - Martin Scorsese.
Ditto. Audrey cited that this was her favourite of her pictures. I'm inclined to say that it was indeed *perhaps* the best movie she did.