Greg Whitespear

En 1862, durante la Guerra de Secesión, dos empresas rivales comienzan a construir la primera línea de ferrocarril transcontinental que enlace el Atlántico con el Pacífico. Al tiempo narra los amores entre la hija de uno de los ingenieros, Mollie Monahan (Barbara Stanwyck), el agente del gobierno encargado de la seguridad Jeff Butler (Joel McCrea) y el principal saboteador Dick Allen (Robert Preston).

The Rangers in New Mexico are being disbanded but Bob Houston gets them to make one more ride. They go after the outlaw gang led by Hashknife. They catch Hashknife, but he escapes taking Barbara with him and Bob and Slim have to go after him again.

Judith Endicott, the daughter of a wealthy eastern banker, vamps Philip Randolph, an Arizonan, when he comes east to talk business with her father. Philip proposes and discovers that Judith has only been kidding him along. He returns angrily to Arizona, and the elder Endicott, accompanied by his daughter, follows him west. With her father's permission, Richard "kidnaps" Judith and takes her to a deserted Indian cliff dwelling, where she must cook and care for him. Bert Durland, Judith's fiancé, follows after her, and his Indian guide steals all of the horses. Judith and Bert and Philip start back to civilization across the desert, and Bert goes berserk from the heat. They are rescued by cowboys, and Judith returns east, "kidnaping" Philip and taking him with her.