Rex (as Rex King of the Wild Horses)
Rinty (as Rin-Tin-Tin Jr.)
Henry
John Sheldon
Alice Ingram (as Lucille Browne)
Frank Nolan
Henchman Raymond
Henchman Jim Luger
Henchman Mack (as Charles Whitaker)
Lewis R. Lou Salters [Ch. 1] (as Dick Alexander)
Sheriff [Chs. 1, 7-8, 11-12]
Henchman Parks [Ch. 1]
Townsman [ch. 1, 7] (uncredited)
Townsman - Chapters 1, 6, 7 (uncredited)
Cowhand (uncredited)
Townsman [Chs. 6-7] (uncredited)
Townsman [Chs. 1, 6] (uncredited)
Dr. R.N. Price [Chs. 6, 11-12] (uncredited)
Townsman (uncredited)
Townsman [Ch. 6] (uncredited)
Deputy Dave (Ch. 6, 7) (uncredited)
Bram Luger [Chs. 1, 6] (uncredited)
Rancher (uncredited)
Lawyer Bronson [Chs. 11-12] (uncredited)
Townsman [Ch. 1] (uncredited)
Spectator (uncredited)
First Deputy [Chs. 1, 6] (uncredited)
Race Track Man [ch. 12] (archive footage) (uncredited)
Henchman (uncredited)
Charles Ingram [Chs. 1, 3, 12] (uncredited)
Townsman [Chs. 1, 6-7] (uncredited)
Lends Alice His Horse [Chs. 6-7] (uncredited)
Gives John Directions [Ch. 1] (uncredited)
Car Passenger [Ch. 6] (uncredited)
Deputy Tom [Chs. 7-8] (uncredited)
Townsman [ch. 6] (uncredited)
Injured Driver [Ch. 4] (uncredited)