Bart discovers Cornelius Van Rennsellaer in the desert, a young man who appears to have an inordinate interest in a rare species of cactus. He's actually a railroad man, he says - his father runs the railroad - and he wants to take the cactus back to St. Louis for breeding.
Corny learned poker at Harvard, and the education was expensive, but he appears to have learned poker well. He wins not only Bart's $300 stake, but his $1000 hideout money as well. That's all right. Corny offers him double the $1300 to impersonate him on the trip to St. Louis, so that he isn't bothered on the ride.
That deal is too good to be true, of course, which is the gist of the story. It's fairly formulaic humor, but fun none the less. Corny has to be in St. Louis in the morning to vote his shares - and another investor wanting to take control of the railroad has sent representatives to ensure that he's delayed so his shares can't be voted,
As a side plot, Edgar Buchanan plays an endearing old card sharp who tries to deal seconds, but doesn't do it too well. Bart realizes it, but willingly loses heavily, to avoid hurting the man's feelings - the checks he writes as Corny will never be honored by the bank because the handwriting will be wrong, so there's no harm, no foul.
As always, this episode features a couple of fetching young actresses. Pippa Scott plays the sweet and innocent one, a niece of Buchanan's, who is too "ethical" to make a play for the railroad heir - so to no viewer's surprise, she decides she really likes that fellow in the baggage car who is fond of cactus. Nita Talbot, five years older, is the sophisticated and dangerous woman, a role she had already been playing for a decade, and would continue to play well into the 1990s. Although Pippa Scott stopped acting in 1984, she once again appeared before the camera 25 years later in the movie "Footprints"