Caterina (Margherita Buy), a nun preparing to take her final vows, stumbles across an abandoned baby and takes it upon herself to find the child's family. This leads her to Ernesto, who assists in the parental search as well as Caterina's search for her own beliefs. Her journey through Milan's working class soon makes her realize that those who hold beliefs not of this world are still bound by humanity and the span of human emotions.