I just finished reading James Bonnet's "Stealing Fire From the Gods."

The book is 20 years of his personal research into storytelling and is one of the most unique screenwriting books I've ever read because it's goal is to provide a totally different approach to writing rather than the typical "have a plot twist ever 30 pages" method.

His approach really goes beyond the nuts and bolts and into the significance of storytelling from a much deeper level suggesting even that all our mythologies are inherent within us which is why since the beginning of storytelling, so many similar archetypes emerge. And this also leads to a reason why storytelling is so valuable.

He references Jungian theory and Campbell's work freely, but still provides his own very specific methodology. It is not light reading.