The film opens with a plan that comes straight from Hell: Satan seeks to ruin Christmas by preventing Jesus’s birth. To carry it out, he dispatches three devils — Tonino Accolla as Astarotte, Oreste Lionello as Scarapino, and Fabio Volo as Farfaricchio — to Naples, rising from the crater of Mount Vesuvius to target the cradle’s capital and tamper with the holy night.
In this bustling Neapolitan setting, a difficult and unhappy boy named Rocco becomes the focal point of Satan’s schemes. He is envious of his soon-to-arrive little brother, Francesco, and bears a constant tension with his mother and father. Amid temptation, the devils coax Rocco into saying the magic word “Opopomoz,” which lets him slip into the crib’s world with a determined goal: to stop Mary and Joseph from reaching Bethlehem. Yet the trio’s mischief quickly spirals out of control, and Rocco ends up fleeing rather than completing the mission.
Meanwhile, Rocco’s cousin Sara — Xsuela Douglas (voice) — is drawn into the mystery when she notices something is amiss. Guided by a curious cat, she ventures into the Crib’s world in pursuit of Rocco, only to be briefly thwarted and later discovered by a young Saint Peter and his family. It is Sara who eventually crosses paths with Rocco, and together they face the consequences of their intrusion. With the help of an Angel, they come to realize that the path they’re on is wrong, and they decide to cooperate to set things right and send the devils away.
Satan, furious at the turn of events, tries one final, darker gambit: he hypnotizes Rocco and targets Sara’s soul. The spell falters when Rocco, moved by Mary’s radiant aureole, unexpectedly shifts the balance. The devils, who have grown tired of their lowly status and the harm they’ve caused, see Sara in danger and choose to act. They rouse Mary and encourage Sara to tap into a grandmother’s song — a remote, powerful lullaby that holds the key to banishing the darkness. The moment Sara sings, the malevolence dissolves, and Satan is pulled back into Hell.
With the danger averted, the Nativity unfolds as foretold. Jesus is born on Christmas night, and Francesco comes into the world, bringing a new sense of hope to the family. The three devils are transformed into humble guardians of the infant: an ox and two donkeys, watching over the newborn, while the town slowly returns to peace and wonder. The story blends fantasy, faith, and family dynamics in a festive, Naples-flavored tapestry, leaving a gentle reminder that even the smallest acts of courage and mercy can illuminate the darkest moments.
