As Earl points out, "The Missouri Breaks" was filmed in 1975 (and released in 1976). It's a truly bad film, but not the worst done on the narrow gauge lines. The honor for that is shared by two equally awful films done on the Durango & Silverton; "A Cold Day in Hell" and "Cole Younger and the Black Train." All three films are steaming piles and I barely gave them mention in my book "Hollywood's Railroads," as doing anything that might encourage anyone to waste their money or time on them would be a huge disservice to readers.