On February 20, 1665, the Inquisition of Lisbon arrested Maria de Macedo, the wife of a midlevel official of the Portuguese Treasury, after she revealed during a deposition that, since she was ten years old, an enchanted Moor had frequently "taken" her to a magical castle in the legendary land of wonders known as the Hidden Isle. The island paradise was also the home of Sebastian, the former king of Portugal (1557--1578), who had died in battle in Morocco while on crusade in 1578. His body remained undiscovered, however, and many people in seventeenth-century Portugal -- including Maria --...