Buchanan (Randolph Scott) rides alone through Texas, en route to his future home of Mexico. He is sidetracked during a stopover in a lawless border town, where Mexican youth Juan (Manuel Rojas) sits in jail, awaiting trial for the killing of the local bully. It seems that the dead man had several influential relatives who intend to string up poor Juan before justice can be served. Championing the boy's cause, Buchanan methodically sets out to undermine the villains by playing one against the other. As was customary in the Randolph Scott-Budd Boetticher films of the 1950s, Buchanan Ride Alone offers unrelenting tension and innumerable plot twists until its explosive finale.