Joseph Campbell
THE HERO WITH A THOUSAND FACES (1968)

The standard path of the mythological adventure of the hero is a magnification of the formula represented in the rites of passage: separation-initiation-return:

A hero ventures forth from the world of common day into a region of supernatural wonder: fabulous forces are there encountered and a decisive victory is won: the hero comes back from this mysterious adventure with the power to bestow boons on his fellow man.

Promethus ascended to the heavens, stole fire from the gods, and descended. Jason sailed through the Clashing Rocks into a sea of marvels, circumvented the dragon that guarded the Golden Fleece, and returned the fleece and the power to wrest his rightful throne from a usurper. Aeneas went down into the underworld, crossed the dreadful river of the dead, threw a sop to the three-headed watchdog Cerberus, and conversed, at last, with the shade of his dead father.