In 1920 Americans were captivated by the childhood diary of Opal Whiteley, an enigmatic young woman from a small town in the Northwest. The diary, which chronicled adventures in the forests of Oregon at the age of seven, was hailed as a revelatory portrait of a child's relationship to God and the natural world. It became an overnight publishing sensation and Opal, then twenty-two, became a celebrity. Yet the diary-and Opal-was soon dismissed as a...