An evil villain steals a newly invented death ray.

Having paid for the education and legal training of his younger brother, Bruce, with the idea that he would become a lawyer and join his business, Frederick Garth, a racketeer posing as an honest businessman, is dismayed when he learns that Bruce has become a G-Man instead.

With the increasing popularity of Republic's sagebrush crooner Gene Autry, rival company Columbia found it necessary to add a musical element to this Charles Starrett Western released in early 1937. As Starrett himself was no singer, the studio hired Donald Grayson to warble Lonesome River, Out in the Cow Country and Pancho's Widow, all by Ned Washington and Sam H. Stept.

Mary Gillespie is restoring the Col. Gillespie Circus to its former splendor after her father's death. With the help of her publicist boyfriend Jim, the sell-out crowds are returning to the big top. Egotistical equestrian star Senor Martinet, however, holds $60,000 of notes signed by the Colonel and due in 24 hours. When a mysterious shadowy figure is seen on the circus lot, and Martinet is murdered in the center ring during his performance, there are suspects aplenty, including Vindecco, Martinet's badly abused hunchback assistant.