In 1917 young Stephen Fermoyle returns to his native Boston as a newly ordained Roman Catholic priest. Upon learning that their daughter, Mona, is planning to marry a Jewish boy, the strong-willed Fermoyle family is so openly rude that the lad changes his mind. Consequently, Mona runs away and becomes the partner of a tango dancer. Stephen's arrogant nature causes the crusty but humane Archbishop Glennon to send him to a remote country parish, and there he learns his first lesson in humility from the dying Father Halley. He discovers that Mona is about to have an illegitimate child and that her life can be saved only if the infant's cranium is crushed. All too aware of Catholic dogma, Stephen denies permission and Mona dies. Haunted by the incident, he takes a year's leave of absence from his position with the Vatican diplomatic corps and becomes a teacher in Vienna. After a romantic but unfulfilled encounter with Anna, one of his students, he decides that the Church is his true vocation. Upon his return to Rome, he irritates most of his superiors by defending the rights of a black priest to have a parish in Georgia. As a result of his courageous fight against the Ku Klux Klan, he is promoted to Bishop. Just prior to World War II, he is sent to Austria in an unsuccessful attempt to persuade Cardinal Innitzer to oppose the Nazis. Subsequently, the two have a narrow escape when the Nazis attack the Austrian diocese. As the war begins, Fermoyle is appointed Cardinal, and his proud family travels from America to watch their son assume the robes of his office.