Abilene gunmen are bent on terrorizing the town of Blue Valley and massacring its inhabitants. They have been hired by local druggist Henry Turner, who has discovered gold beneath the town and wishes complete possession.

Oklahoma outlaw Belle Starr meets the Dalton gang when rescued from lynching by Bob Dalton, who falls for her. So do gang member Mac and wealthy saloon owner Tom Bradfield, who's enlisted in a bankers' scheme to trap the Daltons. Discord among the gang and Bradfield's ambivalence complicates things, as Belle demonstrates her prowess with shootin' irons and horses, and as a surprisingly racy saloon entertainer.

A scientist who is working on a cure for influenza is victimized by his unscrupulous boss, who releases the vaccine before it's ready, resulting in the death of the scientist's son.