The High Chaparral
The Reluctant Deputy (3x21)
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Blue is the victim of a practical joke that finds him enlisted as a temporary lawman
Tricked into being sworn in as a deputy marshal by Manolito and his Uncle Buck, Blue is forced to take the job seriously when the town's regular lawman departs leaving him in charge of the entire town. Blue's new authority enables him to exact a sweet revenge on Manolito and Buck.