Eleanor is the daughter of a strict puritan and Roundhead major and lives in a medieval manor on the bleak wetlands of Somerset. Her longing for color and brightness leads to an obsession with butterflies as well as to an illicit passion for charismatic but troubled Richard Glanville. Richard, the son of an exiled Cavalier, embodies all that Eleanor had been taught to despise and distrust, but he also holds for her all the allure of the forbidden. Her first husband dies, seemingly poisoned, freeing Eleanor and Richard to marry. But can their love survive suspicion and prejudice, a bloody rebellion that makes them bitter enemies, and a superstitious community that stirs up hatred toward her for her love of butterflies? It seems the only peace she can find is in her long-lasting friendship with renowned naturalist James Petiver, a clever young London apothecary who is considered the father of British entomology. But when Eleanor and Richard's son becomes apprenticed to James, tragedy strikes, and Eleanor is forced to embark on a dangerous search for her son that is entwined with a personal quest for truth, freedom, and love.