Jeff Clanton (Robert Ryan) a major in the Union army, captures the remnants of the Quantrill Raiders which include the James brothers as well as the Youngers. Clanton is disposed to let them all go if they take an oath of allegiance, but Mathew Fowler (Robert Preston), the head of the Fowler Detective Agency, a private law enforcement outfit that protects the moneyed interests, has his eyes set on the impressive rewards each of the "badmen" has accrued, setting up what looks to be a pretty good story when Ryan is arrested and faces hanging. He sides with the "badmen" against Fowler, who seems to represent the emerging new order. Claire Trevor, who is supposed to be a saloon girl, is actually married to Fowler, but falls for Clanton. Her character makes zero sense and the movie makes less and less sense as it goes along, a disturbing trend which even the great Robert Preston can't turn around, though he's always worth watching.
Review of Best of the Badmen
