Film based on the book "O Gaúcho" by the writer José de Alencar.
Seeing a black knight, the young man Álvaro runs after him. During the race, the knight falls and he discovers that it is a girl. The two end up falling in love.
Ubirajara, chief of the Araguaias, is engaged to Jandyra. One day, however, he falls in love with Aracy, daughter of Itaquê, chief of the Tocantins and sister of Pojucã, his prisoner. He frees Pojucã so he can declare war on Itaquê and retrieve his daughter. Itaquê is wounded by other enemies and goes blind. The two tribes unite and elect Ubirajara as chief.
