The film""s screenplay was adapted by Frank S.Nugent (director Ford""s son-in-law) from Alan Le May""s 1954 novel of the same name, that was first serialized as a short story in late fall 1954 issues of theSaturday Evening Post, and first titledThe Avenging Texans.Mickey called Rocky a "dead-ass" for his slow reflexes, and he asked: "You sick, kid?" He berated him for his lack of dedication and resolve, and for training like a bum: "You""re training like a ninth-rate pug who oughta be pumping gas in Jersey someplace.His dastardly plan was to kill the parade-goers with lethal green Smylex gas from one of the giant balloons, joking: "If you gotta go, go with a smile.[The greatest difficulty with the film was that five alternative endings were shot (or created in the editing room), and it was undecided how the film would conclusively end.