 There was no official script for the movie, apart from several pages  outlining main dialog sequences. Much of the action/dialog was  improvised and made up by the cast and crew as they went along. This  caused many problems for the editor, Warner E. Leighton (qv), who  never knew what footage was being dumped on him or where in the  movie it belonged. In the DVD audio commentary, he described the  script for the construction site portion of the main pursuit as a  piece of cardboard with a circle on it. Director H.B. Halicki (qv)  pointed at it and said, "Thats the dust bowl. We went around it  twice. Theres your script."