Christopher Vogler, a Hollywood screenwriter and story consultant, synthesized Joseph Campbell’s monomyth ( The Hero with a Thousand Faces ) into a practical 12-stage structure for screenwriting. His book The Writer’s Journey (1992) is the source of this model.
It seems you are referring to based on the model by Christopher Vogler , likely with a typo in the title ( dell 39-eroe → dell'eroe ).