The Girl of the Golden West (1938)

In the 19th century town of Cloudy Mountain, California, Mary Robbins (Jeanette MacDonald) runs the Polka saloon and serenades her customers with her beautiful singing. Also impressed by Mary's voice is bandit Ramirez (Nelson Eddy), a white man raised by natives. Longing to meet Mary personally, Ramirez disguises himself as an officer at a dance, but Sheriff Rance (Walter Pidgeon), who loves Mary and is searching for Ramirez, begins to suspect him -- as does Ramirez's jealous girlfriend.