The Guardians

When crossing through a stretch of land in Arizona Territory now known as Monument Valley, Pietr Raul O'Leary, an illiterate wanderer, encounters a strange, silent man blocking his route. Instead of backtracking and taking a longer route around the solitary guardian, O'Leary decides to press on-a decision that will forever change his life.
A dust storm materializes suddenly; when it passes, O'Leary discovers he is surrounded by a tribe of mysterious people, apparently native to the valley. They tie him up and take him to their village. He is subjected to a series of trials in which he meets a shaman, the chief of the tribe, changing women, ephemeral beings, and a persistent raven. Eventually, he learns that the people, aided by natural monoliths, are guardians of a special way of life.
O'Leary leaves the valley with a message he must share with the rest of the world, but nobody will believe him. A kind, anonymous woman records his words, but the manuscript soon disappears. Years later, the handwritten testament is discovered buried in a desk, bringing to light a valuable lesson for anyone willing to believe the story.