The nephew of a wealthy nobleman, convicted for a forged check, is replaced in prison by a poor engineer. From the exchange of people derives a chain of misunderstandings and messes that ends out well.
In 18th-century Rome, impish aristocrat Onofrio del Grillo amuses himself by playing pranks on all sorts of people — his reactionary family and fellow nobles, the poors, the French occupiers trying to modernize society, and even the Pope himself.
Middle-aged family man Arnaldo is kicked out by his wife because of a misunderstanding. Instead of despairing, Arnaldo takes advantage of the situation to turn around his unsatisfying adult life by going to live in a flat shared with four university students.
Arturo Meraviglia is a struggling impresario who has to take care of Gioele and Rebecca, two children "inherited" by an old uncle. When he realizes that little Gioele has superpowers, his luck changes.
Serafino, a young and innocent shepherd, inherits a huge fortune. He immediately starts spending the entire sum on presents for his friends, causing the envy of his family.