Nuns' lives are filled with service to others, as Caterina's is in working in soup kitchens and sorting and washing clothing to be donated to the poor. But she keeps an emotional distance -- as nuns do -- from those she ministers to; even taking pride in her work is considered a sin. So her preoccupation with the baby is particularly dangerous, and becomes more of an obsession when she decides to search for the baby's parents. The only clue she has is the man's sweater the baby was wrapped in -- a laundry tag on its label leads her to the cleaners shop run by Ernesto (Silvio Orlando), who admits the sweater is, in fact, his. Fortysomething Ernesto now finds himself excited and awakened from his depressing loneliness by the possibility that he may be Fausto's father -- he had a brief affair with Teresa (Carolina Freschi), who used to work for him, and to whom he had lent the sweater.

Caterina and Ernesto are more alike than it would appear at first. Both have, in effect, removed themselves from the world, withdrawn from the human race, and yet seem to find the idea of rejoining it painful and difficult. An awkward and strangely touching scene sees Ernesto and Caterina attending a little birthday party thrown by the girls who work in his laundry for one of their own. Both are startled and delighted by the spur-of-the-moment invitation, and both are obviously unused to this kind of simple, let's-take-a-break-from-work socializing -- Ernesto doesn't even know the birthday girl's name. But chances to become full members of humanity come at many turns: Caterina's mother (Giuliana Lojodice), who has never accepted her daughter's chosen vocation, asks her to leave her order and come home; Ernesto encounters a pretty young woman in a restaurant who leaves her phone number for him. But their constant closing of these open doors has become such a habit that when the abandoned baby seem to extend this invitation once again, neither Ernesto nor Caterina know quite how, or even whether, to accept.

A quiet, moving film, Not of This World feels like a Renaissance painting, in which the play of light and the way its subjects look at one another makes it feel deeper and more meaningful the longer you look at it.