The Simpsons: Season 21
Season 21 Lore Primer
Key plot threads, lore context, and character stakes you need to remember before diving into this season.
- Picks up essential narrative continuity directly following the events of The Simpsons Season 20.
- Character alliances, factions, and personal loyalties undergo significant shifts under escalating stakes.
- Addresses unresolved cliffhangers and thematic mysteries introduced during previous seasons.
- Establishes the primary seasonal conflict that drives serialized character arcs toward the finale.
Episode Guide
Season 21 Progress Shield
Homer the Whopper
Sep 27, 2009 · 22 min
Homer gets the lead in a movie about a superhero who can take on the powers of every superhero in any comic book he touches. To whip Homer into superhero shape, the studio hires a
Bart Gets a 'Z'
Oct 4, 2009 · 23 min
The fourth grade students of Springfield Elementary School decide to spike Ms. Krabappel's coffee in order to teach her a lesson after she takes away their cell phones. She is fire
The Great Wife Hope
Oct 11, 2009 · 22 min
The men and boys in Springfield become obsessed with Ultimate Punch Kick and Choke Championships, a violent sport where fighters inflict severe pain on each other. When Marge and h
Treehouse of Horror XX
Oct 18, 2009 · 23 min
Dial "M" for Murder or Press "#" to Return to Main Menu- Lisa is forced into a Hitchcockian murder scheme by Bart. Don't Have a Cow, Mankind- Springfield is once again overrun by z
The Devil Wears Nada
Nov 15, 2009 · 23 min
Marge and a group called the "Charity Chicks" pose for a calendar in hopes of raising money for charity, but Marge becomes the talk of the town thanks to her racy poses. Meanwhile,
Pranks and Greens
Nov 22, 2009 · 22 min
Principal Skinner is getting fed up with Bart's pranks, so he informs Bart that he is not the best prankster after all. A former student named Andy Hamilton is hailed as the best p
Rednecks and Broomsticks
Nov 29, 2009 · 22 min
Lisa befriends three teenaged Wiccans after getting lost in the woods during a game of hide-and-seek, and must clear her new friends' names when they are accused of cursing the tow
Oh Brother, Where Bart Thou?
Dec 13, 2009 · 23 min
One snowy day in Springfield, Lisa informs Bart that she and Maggie share a bond that Bart will never understand because he doesn't have a brother, so Bart asks Homer for a baby br
Thursdays with Abie
Jan 3, 2010 · 23 min
Grampa is sitting on a bench waiting for his family when a thoughtful-looking man named Marshall Goldman approaches him and asks to hear about his life. Grampa tells Goldman about
Once Upon a Time in Springfield
Jan 10, 2010 · 22 min
Krusty grudgingly adds a pretty, singing cohost named Princess Penelope to his show in order to attract more female viewers. Girls love her, and ratings improve, but Bart and Milho
Million Dollar Maybe
Jan 31, 2010 · 23 min
Homer blows off Marge to buy a lottery ticket and winds up winning the million-dollar jackpot. Fearing how Marge will react if she finds out the reason Homer missed their date, Hom
Boy Meets Curl
Feb 14, 2010 · 23 min
Homer takes Marge out for a romantic evening of ice skating and hand-holding, but upon entering the rink, they encounter a curling team practising. Marge and Homer take to the ice
The Color Yellow
Feb 21, 2010 · 23 min
When Miss Hoover asks her students to research their family history, Lisa is horrified to discover that most of her ancestors were bad people – a motley crew of horse thieves and d
Postcards from the Wedge
Mar 14, 2010 · 23 min
When Bart fails to turn in his homework, Mrs. Krabappel sends a letter home about Bart's behaviour. Despite Bart's best efforts to intercept it, Homer reads the letter, and he and
Stealing First Base
Mar 21, 2010 · 22 min
Principal Skinner announces that Mrs. Krabappel was called out of town and budget cuts dictate that, until she returns, the school's two fourth grade classes will merge. Bart reluc
The Greatest Story Ever D'ohed
Mar 28, 2010 · 23 min
The Simpsons family vacation in Israel with Ned Flanders, but Homer does not appreciate any of the culture—until an Israeli tour guide named Jakob shows him around and, in a severe
American History X-cellent
Apr 11, 2010 · 22 min
When the police are called to diffuse a rowdy crowd at Mr. Burns' estate, one of the officers recognizes priceless stolen paintings on the walls, and the maniacal billionaire is ta
Chief of Hearts
Apr 18, 2010 · 22 min
Homer is completing his court-ordered community service when he befriends his supervisor, Chief Wiggum, by offering him one of his sandwiches. Touched by the act of kindness, Wiggu
The Squirt and the Whale
Apr 25, 2010 · 22 min
The Simpsons decide to embrace a cheaper, alternate source of energy by erecting a wind turbine in their backyard. But when Homer realizes some of the power is being directed to th
To Surveil with Love
May 2, 2010 · 22 min
A bomb squad mistakenly blows up Homer's unattended gym bag, releasing radiation into the city and authorities react by suspending civil liberties. Wiggum and his men install surve
Moe Letter Blues
May 9, 2010 · 22 min
As Mother's Day approaches, Moe narrates an episode in which he writes a letter to Homer, Apu and Reverend Lovejoy, who are vacationing with their children, and threatens to run aw
The Bob Next Door
May 16, 2010 · 22 min
Bart becomes convinced that his new neighbor, Walt, is his archenemy, Sideshow Bob, disguised and back for revenge. But when Marge tries to convince Bart otherwise by taking him to
Judge Me Tender
May 23, 2010 · 22 min
When Moe discovers a hidden talent for judging contests, he is approached by a television agent to join the AMERICAN IDOL judges' panel. Moe flies to Los Angeles where he tours the