With the defection of Gene Autry from the Republic lot, Roy Rogers was truly the King of the Singing Cowboys. In On the Old Spanish Trail, Rogers is for the first time teamed with Latin American singing favorite Tito Guizar. The plot finds Roy and Tito involved with a travelling cowboy tentshow in the modern west. Though there are an abundance of action highlights, the film is lighthearted in nature, as evidenced by the character name of Andy Devine, "Cookie Bullfincher." Rogers and Guizar later costarred with more impressive results in The Gay Ranchero.