"The Great Jethro" features legendary scene stealer John Carradine playing Marvin Bagby, a washed up magician who prefers to go by his stage name, Marvo the Magnificent, as he unsuccessfully tries to obtain a loan from Mr. Drysdale's bank. Alas, his magic equipment has been locked up for 10 years (unpaid back rent), so he's been selling aluminum awnings and mufflers, until his most recent employment at a car wash (the initial amount of $50,000 turns out to be a mere $50!) Meanwhile, Jethro figures to get work at Drysdale's bank, but gets sidetracked by a chance encounter with the down and out magician, who sees an opportunity to swindle the simple minded pigeon by performing a magic show for the entire Clampett family. Everything one would expect from the veteran character actor, whose tailor-made role is performed with lip smacking relish.