At a charity comedy show, Krusty discovers that his brand of humor is out of step with modern stand-up comedy. After announcing his retirement and going on a drunken bender, Krusty wakes up at the Simpsons household and, with the help of Bart Simpson and special guest star, Jay Leno, Krusty becomes an anti-establishment stand-up comic (''a la'' GeorgeCarlin, Denis Leary, DennisMiller, and Bill Hicks), but must choose between his ethics and selling out when an agent offers him the chance to be the spokesman for a new SUV called The Canyonero.

!!"The Last Temptation of Krust" contains examples of:
* AsianSpeekeeEngrish: Krusty's offensive Asian impression: "ME SO SOLLY!"
* TheDeadRiseToAdvertise
-->''So I'm watching TV today, and all I keep seeing is dead celebrities hawking products! You've got poor old Vincent Price floating around in a toilet keg telling me about ''the horrors'' of an unfresh bowl! And I hardly think Winston Churchill would eat at a place called "Der Wienerschnitzel"!''
* DudeNotFunny: The InUniverse reaction to Krusty's racist performance.
* FakeOutFadeOut: Near the end, after the Canyonero commercial song appears to finish, the 20th Century Fox Television VanityPlate appears...only to get pushed aside for more of the Canyonero song.
* HummerDinger: The Canyonero.
-->"Twelve yards long, two lanes wide, sixty-five tons of American pride! ''[[EarWorm Canyonero!]]''".
* NotAllowedToGrowUp: {{Lampshade|Hanging}}d. When Marge bought Bart and Lisa new shoes, Lisa complained the shoes were too big and Marge said they'll fit when the kids grow up. Bart then asked when it'd happen like he didn't expect it to happen.
* ProducePelting: Krusty after selling out at Moe's.
* ProductPlacement: Krusty promoting the Canyonero during his comedy act.
* SpitTake: Marge at the comedy show when JaneaneGarofalo opened her act with, "I got my period today."
* StrangeMindsThinkAlike: A couple people thought Krusty died.
* TakeThat: When Krusty bombs at the comedy show making a joke about TV dinners, Janeane Garofalo sarcastically quips "Ooh, take that, Swanson's".
* TemptingFate: During Krusty's performance at the comedy show.
-->'''Jay Leno:''' What's he gonna do next? A flapping dickie?
-->'''Krusty:''' Uh-oh, I'm losing them. Better give them the "A" material! Hey-hey! ''(flaps dickie)''
* UnusuallyUninterestingSight
-->'''Homer (as he's walking in to use the bathroom):''' I didn't know you, Jay Leno and a monkey were bathing a clown.
* ValuesDissonance: InUniverse. Krusty's outdated and offensive comedy act fails to impress the audience.