Mary-Lou (Ma) Jordan, is a tough, ambitious frontierswoman with a paranoid hatred of Indians. When the story opens, in 1869, Mary-Lou and her two daughters, Ellie-May and Sara-Jane are alone on their small Texas ranch, the Circle J. The ranch is attacked by the Anderson gang, on the run following an abortive bank raid in Fort Worth. Mary-Lou outmaneuvers them and the Anderson brothers are badly wounded and captured. Meanwhile, Jim, her husband, returns from a cattle drive to Fort Worth with the news that Mary-Lou has inherited a huge ranch (the Flying W) in Arizona. Determined to grasp the opportunity, Mary-Lou persuades her husband to consider moving, while she and Hardy, their second son, set out to look the ranch over. Along the way they fight off outlaws and Indians and meet up with Clay Wallace, a young Easterner gripped by gambling fever. Hardy decides to stay on in Arizona and straighten out the ranch, while Mary-Lou returns to Texas. After hearing his wife's views, Jim Jordan reluctantly agrees to sell the Circle J to Dunc Patterson, an ambitious local rancher. The story concludes with the Jordan's, complete with wagons, remuda and trail herd, setting out for Arizona
