Once On This Island takes a Caribbean twist to the traditional Little Mermaid tale, and tells the story of Ti Moune, a poor peasant girl who falls in love with Daniel, an upper class boy whose life she saves after a car crash. Central to the story are four gods that the peasants believe rule their lives. The gods of Love, Earth, Water, and Death cause the lives of the young lovers to intersect and send Ti Moune on the fateful journey that tests the strength of her love.