The bandit Pancho Vanilla robs a bank in Mexico and returns to his hideout in a hurry so he can see how much he got. However, the fastest mouse in Mexico is following him, with intent to return the money because poverty will cause people to eat all the crumbs, leaving the mice with nothing to eat. He challenges Pancho to a duel, and during the duel Speedy is able to return the money by going past him over and over again. He brings the money back to the bank, and an enraged Pancho shoots his feet. Later, when Pancho sets various traps for Speedy to prevent the mouse from taking the stolen money back, Speedy tricks the bandit into falling into his own traps. Speedy manages to get all the money back to the bank, only for a defeated Pancho get his revenge and mess up Speedy's money-counting progress in the bank.
David H. DePatie and Friz Freleng receive onscreen credit as producers for the very first time, marking the first cartoon in twenty years since the Leon Schlesinger era where Looney Tunes cartoon producers receive onscreen credit, and the first cartoon to do so since "Buckaroo Bugs" (1944).
Pancho Vanilla resembles Yosemite Sam with a Mexican accent.
By this point, all new Looney Tunes and Merrie Melodies shorts produced until 1969 would feature the modernized "Abstract" WB opening/closing logos (taken from "Now Hear This", "Bartholomew Versus the Wheel" and "Señorella and the Glass Huarache"), with a "klunky" rendition of "The Merry-Go-Round Broke Down" arranged by Bill Lava, however future cartoons would change the color of the background from white to black.
The Merrie Melodies Show version of this cartoon's title card (as pictured in the "Gallery" below) depicts both Speedy Gonzales and Yosemite Sam together, even though the cartoon itself doesn't co-star Yosemite Sam; instead it co-stars Pancho Vanilla.