 The bartender was in fact an agent employed by the Peterson (in real life, Pinkerton) Detective Agency sent to investigate and provide information about the Reno Brothers' crimes.His replacement is Scott's character, James Barlow, a former secret agent for the Confederacy, who determines to join the gang by posing as a train robber, a ploy which is aided by his being allowed to pull off a staged train robbery (with the full cooperation of the train crew) in the area.