On the night before Christmas, three little devils are sent to Naples by “His Profundity”, the Lord of the Inferior Regions, with the terrible mission of eliminating Christmas. To do so, they have to find a human willing to impede the birth of Jesus. Meanwhile, a peaceful and friendly family is about to merrily celebrate a double Christmas: on Christmas Eve will be born a son, right on the birthday of Baby Jesus. All are awaiting the arrival of little Franceschino, as he will be named, except for Rocco, the older brother of the future newborn who, jealous and worried he will lose his parents' love, would “do anything” to remain an only child…
The three little devils choose Rocco…