After his brother Robeson disappears without a trace while exploring Africa in search of a legendary 'white tribe', Allan Quatermain decides to follow in his footsteps to learn what became of him. Soon after arriving, he discovers the Lost City of Gold, controlled by the evil lord Agon, and mined by his legions of white slaves. Allan Quatermain once again teams up with Jesse Huston where the discovery of a mysterious old gold piece sends Quatermain looking for his long-lost brother, missing in the wilds of Africa after seeking a lost white race.