A handsome young American, Otis Madison volunteers for the French Foreign Legion to fulfill an urgent, personal mission - to find his old, childhood playmate, John Geste, rescue him from the horrors of a military prison in the African desert and bring him home to his sweetheart Isobel (Lorettta Young). Thwarted by a fanatical force of Arab tribesmen, the unrelenting harshness of the scorching, desert sun, blinding sandstorms and forced marches, the American born legionnaire is undeterred from his heroic quest.