Mythology for centuries has served as humanity's window into understanding its distant past. In our modern world, storytelling creates its own myths and legends, in media ranging from the world of television and cinema to literature and comic books, that help us make sense of the world we live in today. What is the "Mytharc"? How did it arise? How does it inform modern long-form storytelling? How does the classical hero's journey intersect with modern myths and narratives? And where might the storytelling of tomorrow take readers and viewers as we imagine our future? From The X-Files to H.P. Lovecraft, from Lost to the Marvel cinematic universe and many worlds beyond, this study explores our modern storytelling mythology and where it may lead us.