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THE SIMPSONS · SEASON GUIDE

The Simpsons Season 21

7.8 · GREAT Sep 27, 2009 – May 23, 2010 FOX 23 EPISODES ★ 7.8 AVG EPISODE
EPISODE RATINGS · E01→E23 The Simpsons season 21 episode ratings: 23 rated episodes, from 6.9 to 8.5; highest E14
TURN THE DIAL S01 S02 S03 S04 S05 S06 S07 S08 S09 S10 S11 S12 S13 S14 S15 S16 S17 S18 S19 S20 S21 S22 S23 S24 S25 S26 S27 S28 S29 S30 S31 S32 S33 S34 S35 S36 S37 S38

The season in brief

Season 21 of The Simpsons aired from Sep 27, 2009 – May 23, 2010 on FOX and runs 23 episodes.

FAN DESK VERDICT A strong year with only a couple of skippable detours. Watch it straight through — the map below flags the peaks.

Must-watch episodes

TOP RATED

Episode map

FAN RATINGS
ESSENTIAL GREAT SOLID FOR COMPLETISTS
8.5
FAN DESK PICK OF THE SEASON
Episode 14 — Postcards from the Wedge

Every episode

23 IN ORDER
S21E01 Sep 27, 2009 30 MIN ★ 7.6

Homer the Whopper

Comic Book Guy casts Homer as the lead in "Everyman," a feature film based on a new comic book superhero who possesses the ability to take on the powers of every superhero in…

S21E02 Oct 4, 2009 30 MIN ★ 7.7

Bart Gets a 'Z'

When Mrs. Krabappel confiscates student's cell phones, the class, organized by Bart, decides to teach her a lesson by spiking her coffee and watching her make a drunken fool of…

S21E03 Oct 11, 2009 30 MIN ★ 7.4

The Great Wife Hope

The men and boys of Springfield become obsessed with Mixed Martial Arts, a violent sport where fighters inflict severe pain on one another. When Marge and her friends stage a…

S21E04 Oct 18, 2009 30 MIN ★ 8.4

Treehouse of Horror XX

In the 20th anniversary of THE SIMPSONS annual "Treehouse of Horror" Halloween special, three chilling tales of Halloween horror unwind. First, Lisa becomes livid with Miss…

S21E05 Nov 15, 2009 30 MIN ★ 8.2

The Devil Wears Nada

In an effort to raise money for charity, Marge and "Philanthro-Chicks" decide to pose for a calendar. At the photo studio, Marge is a bit reluctant to reveal any skin, but the…

S21E06 Nov 22, 2009 30 MIN ★ 7.6

Pranks and Greens

Fed up with Bart's constant pranks, Principal Skinner tells Bart that there is a former Springfield Elementary student hailed as the best prankster ever - even better than Bart -…

S21E07 Nov 29, 2009 30 MIN ★ 6.9

Rednecks and Broomsticks

After getting lost in a game of hide-and-seek, Lisa wanders into the field and discovers three teenage girls, including Cassandra, who are practicing Wiccans. Though she is…

S21E08 Dec 13, 2009 30 MIN ★ 8.2

O Brother, Where Bart Thou?

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…

S21E09 Jan 3, 2010 30 MIN ★ 7.7

Thursdays with Abie

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…

S21E10 Jan 10, 2010 30 MIN ★ 7.3

Once Upon a Time in Springfield

In the landmark 450th episode of THE SIMPSONS, Krusty is approached by two network executives who want to bring on female co-star Princess Penelope to increase the show's female…

S21E11 Jan 31, 2010 30 MIN ★ 7.9

Million Dollar Maybe

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,…

S21E12 Feb 14, 2010 30 MIN ★ 8.0

Boy Meets Curl

Homer takes Marge out for a romantic evening of ice skating and hand-holding, but upon entering the rink, they encounter a curling team practicing. Marge and Homer take to the ice…

S21E13 Feb 21, 2010 30 MIN ★ 7.5

The Color Yellow

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…

S21E14 Mar 14, 2010 30 MIN ★ 8.5

Postcards from the Wedge

When Bart fails to turn in his homework, Mrs. Krabappel sends a letter home about Bart's behavior. Despite Bart's best efforts to intercept it, Homer reads the letter, and he and…

S21E15 Mar 21, 2010 30 MIN ★ 7.8

Stealing First Base

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…

S21E16 Mar 28, 2010 30 MIN ★ 7.5

The Greatest Story Ever Doh'd

When Homer is playing noisily in the yard, it disrupts Flanders' bible-study group. Coaxed by the reverend, a frustrated Flanders takes it upon himself to redeem Homer by inviting…

S21E17 Apr 11, 2010 30 MIN ★ 7.2

American History X-cellent

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…

S21E18 Apr 18, 2010 30 MIN ★ 8.0

Chief of Hearts

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,…

S21E19 Apr 25, 2010 30 MIN ★ 8.0

The Squirt and the Whale

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…

S21E20 May 2, 2010 30 MIN ★ 7.9

To Surveil with Love

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…

S21E21 May 9, 2010 30 MIN ★ 8.0

Moe Letter Blues

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…

S21E22 May 16, 2010 30 MIN ★ 8.3

The Bob Next Door

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…

S21E23 May 23, 2010 30 MIN ★ 8.2

Judge Me Tender

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…

Cast this season

MAIN CAST

Where to watch season 21

US · NOVEMBER 2026
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Season 21 FAQ

How many episodes are in The Simpsons season 21?

The Simpsons season 21 has 23 episodes.

When did The Simpsons season 21 air?

The Simpsons season 21 aired from September 27, 2009 to May 23, 2010.

Where can I watch The Simpsons season 21?

In the US, The Simpsons season 21 is available on FX, Hulu, Disney+, fuboTV, DirecTV On Demand, Spectrum On Demand, YouTube TV, FOX One Amazon Channel, Hulu on Disney+, Amazon, Fandango at Home, and AppleTV.

What is the best episode of The Simpsons season 21?

The highest-rated episode of The Simpsons season 21 is S21E14 “Postcards from the Wedge”, rated 8.5/10.