By studying various myths and folk tales, along with cinematic portrayals of otherworldly experiences, commentary from modern individuals, and reports from traditional shamans who are experts at traversing the Otherworld reality, this text discerns the features and characteristics of this supernatural realm. Contemporary research into the Otherworld marks this realm as corresponding to the unconscious substratum of the human psyche, what C.G. Jung referred to as the collective unconscious. Certain scientists have found evidence of its connection with various aspects of brain functioning, suggesting that the brain in many ways encourages a belief in the Otherworld. However, it would be a mistake to call the Otherworld a figment of the human imagination, since this realm seems to have a type of physical existence.
The book considers the Otherworld to exist and provides reasons why rational-thinking individuals are hesitant to accept its existence even when their brains are telling them: the Otherworld is real, and you have just experienced it.