Filmed adaptation of the famed peasant girl who sees holy visions of the Virgin Mary at a grotto which soon spawns healing waters in Lourdes. Eventually she joins a convent, but dies at a young age, but becomes sainted by the Vatican.

In 1858, while gathering wood in a grotto near Lourdes, Bernadette Soubirous, the sickly, uneducated daughter of a poverty-stricken family, sees a white-clad "lady" who speaks to her in a soft voice. When news of this vision circulates throughout the village, the girl's parents forbid her to return to the grotto. But her friends persuade her father to allow her to go back, and each time she does so the vision reappears. On a subsequent visit, Bernadette follows the lady's instructions and scratches at the earth until a spring bursts forth. Opinion remains divided, however, as to the validity of Bernadette's reports, and the local priest questions her about the identity of the lady. Bernadette again goes to the grotto and returns with the lady's response, "I am the Immaculate Conception." Later, a sick child drinks from the spring and is cured. As word of this miracle spreads and thousands of believers journey to the spring to pray and be cured, the governor erects barricades around the grotto. However, Emperor Napoleon III eventually decrees that free access to the miraculous spring is to be granted to all. Bernadette retreats to a convent at Nevers and becomes Sister Maria Bernarde. Even here, she is the object of curiosity and misunderstanding as well as reverence. Her delicate health gradually weakened by asthma attacks, she dies on April 16, 1879.