Gaucho Serenade

Gaucho Serenade is a 1940 American Western film directed by Frank McDonald and starring Gene Autry, Smiley Burnette, and June Storey. Written by Betty Burbridge and Bradford Ropes, the film is about a singing cowboy who goes up against a group of businessmen who plot to kidnap the son of a former partner so he wont testify against them.

Ronnie does not know that his father, Frederick Willoughby Lester Matthews, is actually in San Quentin State Prison, framed for embezzlement by his employer, Edward Martin Joseph Crehan of the Western Packing Company, to cover his own criminal activities. Willoughby agrees to appear as a witness on behalf of the small independent ranchers of California in a lawsuit against Martin, who has been driving them out of business to gain a monopoly. To prevent Willoughby from testifying, Martin schemed to kidnap Fredericks son Ronnie by sending the boy the cable that invited him to visit his fathers large spread, Rancho San Quentin. The plot was momentarily derailed when the boy mistook Gene and Frog for his escorts.Gene recognizes Willoughbys name and suspects that something is not right. He decides to retain custody of the boy until he can investigate. While driving along the road, they nearly collide with Joyce Halloway June Storey and her little sister Patsy Mary Lee, whose car goes into a lake. Joyce is a socialite, a wealthy ranch owner, and a runaway bride who is wanted by the police for taking the jilted bridegrooms car. She and Patsy stow away in Genes horse trailer, and after several spats, Gene agrees to drive them to their California ranch. Along the way, Jenkins and Carter, having picked up Ronnies trail, try to kidnap the boy, but Gene and Frog foil the attempt. ........

Source: Wikipedia