In N'Gombi, Nigeria, British District Commissioner R.G. Sanders (Leslie Banks) oversees various tribes. Discovering that a Liberian native, Bosambo (Paul Robeson), has been acting as chief without approval, Sanders nevertheless is impressed by Bosambo's skills and allows him to remain chief. With Sanders' aid, Bosambo holds off an attack by rebel Mofolaba, and for the next five years peace reigns at the river. However, when Sanders heads to England to marry, Mofolaba returns, vowing revenge.