Jack tells the valet that his rental period is up (a week for $5.00, equal to $52.26 today) and he needs the suit because he is taking Mary Livingstone out for her birthday, and, true to character, is looking for a good cheap restaurant.

", and then an exchange is heard where Ed, apparently having been in the vault for a long time, asks "We win the war yet?"

Mary arrives while Jack is inspecting his cheese vault, and he emerges wondering who has been pilfering his best gorgonzola.

As they discuss their options, the cat writes a message extolling the "Kit Kat Club" ("entertainers admitted free") and sends it to Jack as a paper airplane.

Jack and Mary putter off in his Maxwell with Rochester behind the wheel until they reach the Kit Kat Club by following the arrows pointing to it.

While en route, Mary asks for champagne, while Jack says that he prefers a good "mousecatel".

as the camera cuts to the live-action Jack Benny, who wakes up and, breaking the fourth wall, tells the audience: "Gee, what a crazy dream!

Written by Tedd Pierce, it is a parody of The Jack Benny Program starring the voices of Jack Benny, Mary Livingstone (in her final public performance), Don Wilson and Eddie "Rochester" Anderson as rodent caricatures of their respective radio and television characters, with Mel Blanc reprising his imitation of Benny's Maxwell automobile (also assuming the voice of "Ed", Jack's underground vault guard, usually portrayed on radio and TV by Joseph Kearns).

The Mouse That Jack Built is available on Looney Tunes Golden Collection: Volume 3, Disc 2.