Argentina, 1875. On the death of his father, Don Miguel returns to his country to take the reins of the family hacienda. There he finds Martin, a childhood friend he considers his brother. From warm, the reunion turns to stormy when Martin kills the cowboy who refuses to drink when the prodigal son returns. Now an outlaw, he strives to preserve the great plains of the pampas by preventing the railroad from crossing them with weapons. Hunted by Major Salinas whose life he nevertheless preserves, weakened by his love for the beautiful Teresa Chavez, Martin tries to flee to Chile ...