Watch FMovies. Conchita Cordova sings in the cathedral choir in her village of San Miguelito near the Rio Grande. Millionaire oil man John Rannie, whose oil fields have displaced the peasants, desires Conchita, and when he learns that her fiance, Juan Mendoza, has been employed by Adolf Wylie, a German spy, Rannie threatens to expose Juan unless Conchita gives herself to him.