Bookish Dr. Cardwell is not very popular with the people of the small town of Big Bend, who prefer the charismatic Dr. Ginder. Cardwell has few paying patients and cannot even pay his grocery bill. One night he is visited by Red Bastian, a notorious outlaw in need of some quick medical attention. Bastian takes a liking to Cardwell and gives him a hundred-dollar bill as payment, which the doctor uses to square things with the grocer. Before their next bank robbery, Bastian’s gang picks up a pretty hitchhiker. She manages to escape during the shootout, but is wounded. Dr. Cardwell takes care of her at his home and grows fond of the girl, named Jo. All of Big Bend is in a tizzy about Red Bastian, with many folks believing that Jo is his moll. Cardwell is blindfolded and brought to Bastian’s hideout to check on his wound, but the doctor is able to deduce the location. Meanwhile, the G-men tracking the gang have traced the stolen hundred-dollar bill back to Dr. Cardwell. Cardwell is willing to meet up with the cops, but learns that Bastian has kidnapped Jo. Returning to Bastian’s hideout the doctor convinces the gang to get vaccinated against a tainted water supply, injecting them instead with a sedative that will allow the feds to round up the gang while Cardwell and Jo escape to safety.