Politically ambitious Amarillo police chief Jack McGinnis uses a local murder to gain votes in his campaign, a setback for Sheriff Buck Olmstead, up for re-election. The situation looks better for Olmstead after FBI agent Frank LaCrosse arrives to track the killer. LaCrosse has a personal agenda: he’s convinced this killer is the man who kidnapped his son. Meanwhile, ex-medical student Lane Dixon, hitchhiking across New Mexico, gets a lift from friendly Bob Goodall, a former rail worker who later rescues Dixon from menacing miners in a bar. Red herrings throughout conceal the true identity of the killer.