The Hero with a Thousand Faces argued that a single underlying story, the monomyth, structures hero narratives from every part of the world: a call to adventure, a crossing into a world of trial, a supreme ordeal, and a return bearing a boon for the ordinary world. Campbell drew his comparisons from Greek, Indian, Native American, Polynesian and biblical material alike, reading the pattern through a broadly Jungian lens as an expression of universal psychological structures rather than of historical borrowing between cultures. Folklorists and anthropologists have long pushed back on the method: the pattern, critics argue, is loose enough to fit almost any narrative once fitted to it, and Campbell's comparisons flattened real differences of context, function and belief between the traditions he drew on.
Whatever its standing as ethnography, the monomyth became one of the most consequential ideas to cross from academic myth studies into popular culture. George Lucas has credited it directly with shaping the structure of Star Wars, and the hero's journey subsequently became a stock tool of screenwriting manuals and story consultants across Hollywood. Campbell's late television conversations with Bill Moyers, broadcast in 1988 as The Power of Myth shortly after his death, carried the same ideas, mythology as a living guide to inner life rather than an antiquarian record, to millions of viewers who never opened his books.