Wide Sargasso Sea is based on the 1966 postcolonial novel of the same name by Dominican-born author Jean Rhys. As with many postcolonial works, it deals with the themes of racial inequality and the harshness of displacement and assimilation.
The novel is essentially a prequel to Charlotte Brontë's Jane Eyre (1847), telling the story of the first Mrs Rochester, a white Creole heiress caught in an oppressive patriarchal society in which she belongs neither to the white Europeans nor the black Jamaicans. Antoinette is a young female landowner who marries an Englishman (newly arrived in Jamaica) to avoid losing her property. All seems perfect, love arises, and happiness is on the way, but she is hiding an old secret regarding her childhood and her mother. The secret slowly begins to erode this perfect relationship and the young lovers are swept into a menage of black magic and erotic obsession that spirals into a climax of seduction, betrayal, and ultimately revenge.