Witnesses believe an explosion at a hermitage high in the Tuscan Apennines is a miracle. When a body is not found in the rubble, the Church concludes Brother Pietro, a hermit, must have been propelled into heaven. Though devout, the brother has a secret past. Father Sergio, assistant to the bishop, asks Sister Angela to live among the monks in the monastery and verify the miracle for the Church.Living among the monks in the monastery on the mountainside below, Sister Angela elicits the help of Brother Salvatore, a congenial mystery-reading monk, who offers his spare time to help her explain the dazzling display.Sister Angela soon discovers that though devout, Brother Pietro has a secret past. Broken vows and ties to big business create a web of deceit. But the nun is forced to also investigate the Church in order to solve the mystery.