The title and plot are a reference to the essay Message to Garcia.
The plot of this cartoon involves Mexican Revolutionary mice. Numerous attempts to deliver a message to General Gracias fail when every messenger is caught by Sylvester. Desperate, Speedy Gonzales is used to deliver the message. After overcoming several of Sylvester's attempts to thwart him, Speedy delivers the important message to the general only for it to turn out to be "Happy Birthday". He promptly cuts the "pussy gato" out of his bonds and lets him chase off Gracias and his consort.