"Amidst the religious fervor of the Second Great Awakening, John Humphrey Noyes, a spirited but socially awkward young man, attracted a group of devoted followers with his fiery sermons about creating Jesus'' millennial kingdom here on earth. Noyes and his followers built a large communal house in rural New York where they engaged in what Noyes called "complex marriage," an elaborate system of free love where sexual relations with multiple partners...