Synopsis by Hans J. Wollstein
B-Western regulars Jack Perrin and Marilyn Mills starred in this obscure, low-budget Western serial released in 15 chapters. Mills, a Dutch-born equestrienne, was famous for working with her horse Beverly and has been credited by some with the discovery of Gary Cooper. Riders of the Plains is remembered only as one of the early films of Boris Karloff, who played a supporting role. Also appearing in the cast, Rhody Hathaway was the father of director Henry Hathaway.