At the Shanghai University School of Medicine in early 1951, the Communists, informed of the resistance of Catholic students (about 160), sent Party members to try to re-educate them. After months of fruitless efforts, the militant atheists were ready to give up.
Then, one day, two Catholics publicly announced that they were rejecting the faith of their baptism. A young woman joined them, throwing her Rosary to the floor in the middle of the room. It fell at the feet of a Catholic student who managed to pick it up discretely. He broke its string and gave a bead to each Legionary of Mary in his group, saying: "Keep these grains very carefully, for if we pray faithfully, the Blessed Virgin will do a miracle!”
For three months, all kept praying for that intention. Then one day the young apostate appeared before all the members of the Legion of Mary, asking for their forgiveness. Then everyone brought back the beads that they had kept ... The profaned Rosary was reassembled with a new string and returned to the repentant legionary! The Blessed Virgin had done a miracle!
Collection of Marian Stories, 1976