 Utilizing a script from 1939 s "She Married a Cop" with a 1946 Hit Parade song for the title, Gene Autry s screen return following his WW II Army Air Corps service, "Sioux City Sue" has Hollywood talent scout Sue Warner (Lynne Roberts) in search of a singing cowboy and finding and offering cattle rancher Gene Autry (Gene Autry) a contract. He agrees to go to Hollywood if there is a part for his horse Champion. Gene isn t aware they only want to use his voice in an animated cartoon. After the preview, he and Champ depart in a huff (Well, actually, Champ was in a trailer). The annoyed Sue also follows and gets work on Gene s ranch as a cook. Later, the studio heads, while looking at Gene s screen test, decide he is a natural and want to sign him to a contract. After a few misunderstandings, Gene realizes that Sue is sincere, and he signs a contract to star in a musical western, but first he has to stop a cattle stampede and rout a gang of rustlers trying to blow up his ranch dam.