Two half sisters, Effia and Esi, unknown to each other, are born into two different tribal villages in 18th century Ghana. Effia will be married off to an English colonist, and will live in comfort, raising half-caste children who will be sent abroad to be educated in England before returning to the Gold Coast to serve as administrators of the Empire. Her sister Esi will be imprisoned beneath Effia in the Castle's women's dungeon, before being shipped off on a boat bound for America, where she will be sold into slavery.