Rare Times The Simpsons Actually Made Sequel Episodes

Most sitcoms operate with a soft reset button. No matter how wild a plot might be in any particular episode, the status quo of the series is always restored by the episode's end, and/or the events are simply ignored in subsequent episodes. Gilligan and the rest of the castaways are never any closer to getting off the island from one episode to the next, and no matter how many disasters he causes in the Winslow home, Steve Urkel is always welcomed back in the next week. "The Simpsons" is extremely faithful to the reset-button concept: not only has Springfield, USA gone mostly unchanged since the show first broadcast in 1989, but its characters haven't aged. Bart Simpson remains an eternal 10-year-old boy; in real life, he'd be in his early 40s by now.

But every so often the show will reach back into its storied history and make an episode that directly follows up on a previous episode, years or even decades later. Some of these are quick nostalgia grabs, others check in on a beloved (or controversial) guest character from years past, and still others have kept one particular storyline going long after its natural end date. Here are the rare times "The Simpsons" actually made sequel episodes.

A visit from the area's Bing Crosby-esque parson in Season 20's "Wedding for Disaster" reveals that Rev. Lovejoy was accidentally unlicensed for several months, making any ministerial duties performed during that time invalid — including Marge and Homer's second marriage from Season 8's "A Milhouse Divided." In that episode, Homer, fearing that he will suffer the same fate as Milhouse's recently divorced father Kirk, divorces Marge so that they can get married all over again. With the revelation that their second marriage wasn't sanctified, Marge takes the opportunity to plan the wedding she's always dreamed of, only to transform into a literal bridezilla. When Homer doesn't show up for the ceremony, Marge fears that her demanding ways and short temper scared him off, but in reality, certain interested parties have kidnapped Homer in order to keep the wedding from happening.

As with "The Old Blue Mayor," the episode uses its connection to a previous episode to introduce a mostly unrelated plot, though it does include a cameo from someone we'll see later in the list, Sideshow Bob. When Bart and Lisa find an "SB" keychain at the scene of Homer's kidnapping, they immediately suspect their old nemesis, but it turns out that he's innocent, having spent the day with his former nemesis, Krusty the Clown, sculpting and watching "The House of Sand and Fog."

Season 13's "I Am Furious Yellow" introduced the world to "Angry Dad," the show's take on the late-'90s web cartoon "Angry Dad" featuring a crudely animated Homer getting uncontrollably angry at every little thing. The cartoon, written and animated by Bart, becomes an unexpected hit, leading Homer to reconsider his relationship to rage and attempt to be more mindful — that is, until a series of events turns him into the Incredible Hulk. Nine years later, "Angry Dad" returns in Season 22's "Angry Dad: The Movie." When the cartoon's current rights holder (an office chair company) wants to make a movie out of Angry Dad, the resulting short becomes an awards darling. As the accolades keep rolling in, Bart becomes jealous that Homer is hogging all the attention.

The episode doesn't really follow up on the themes of "I Am Furious Yellow." For one thing, Homer never really gets angry in this episode, which is perhaps a commentary on the way Homer was written in 2011 as opposed to 2002. The bulk of the jokes come from the episode clowning on awards shows and its own genre, parodying "The Triplets of Belleville," "Wallace and Gromit," and the awards domination of Pixar, among others. Ricky Gervais guest stars in a fairly brutal send-up of himself.

One of the show's rare permanent changes came in Season 11's "Alone Again, Natura-Diddily" when the show killed off Maude Flanders after a contract dispute with actress Maggie Roswell. Her death has been referenced throughout the rest of the series, as in "Brawl in the Family" and Ned's long-running romance with Mrs. Krabappel. But Ned's widowhood and bereavement are rarely the focus of an episode, with the exception of Season 12's "I'm Goin' to Praiseland." When a would-be tryst with a beautiful contemporary Christian singer (Shawn Colvin) ends with Ned cutting her hair in the night to make her look like Maude, everyone realizes that he needs some help moving on. In the process of cleaning out Maude's belongings, Ned finds an old sketchbook of Maude's that includes designs for a religious theme park called Praiseland. Inspired, he works to make Maude's dreams into reality.

Once the park is complete, Ned makes an incredible discovery: When people get near the giant statue of Maude at the center of the park, they experience incredible visions. Visitors flock to see this supposed miracle until Ned is informed that the visions are being caused not by divine intervention, but by a gas leak. Praiseland is closed, and with it, Ned is able to move on with his life.

Like Jackie Mason as Rabbi Krustofski, many of the show's sequel episodes are built around notable guest characters and/or stars. One of the most recent of these is Zooey Deschanel as Cletus the slack-jawed yokel's talented daughter, Mary Spuckler. First appearing in Season 19's "Apocalypse Cow," Mary helps Bart raise a calf for the 4-H Club, but their burgeoning romance soon turns very serious when the Spucklers interpret Bart's gift of the now-grown cow as a marriage proposal. 

Five years later, the show begins Season 24 with "Moonshine River," in which the family takes a lovelorn Bart to New York to find Mary, who has been living the life of a glamorous urbanite. Later in that same season, "Love Is a Many-Splintered Thing" has Mary back in Springfield, as Bart narrates their brief rekindled romance from some future point a la Woody Allen in "Annie Hall." He wins her back only to lose her once again.  It seems Bart and Mary's relationship will never quite work, although there's nothing to stop Deschanel from returning to Springfield for one more song.

Jon Lovitz's obnoxious Artie Ziff has been a thorn in the sides of Homer and Marge since they were in high school. As seen in the Season 2 flashback episode "The Way We Was," Artie asks Marge to the senior prom. He dazzles Marge's parents and sisters (as opposed to her previous date, Homer, who horrified them), but when he forces himself on her in his car, she rebuffs him. Artie would appear briefly in the Season 4 episode "The Front," voiced by Dan Castellaneta, but Lovitz wouldn't revisit the role until Season 13's "Half-Decent Proposal," in which a now-wealthy Artie offers Marge $1 million to spend a weekend with him, which Marge reluctantly accepts. Of course, Homer is the only man for Marge, a fact that Artie sadly accepts by the end of the episode.

Two seasons later, a now-broke Artie is discovered living in the Simpsons' attic in "The Ziff Who Came to Dinner." Having lost his company in the 2000s dot-com bust, he turns to the family for help, but soon is revealed to have ulterior motives. Artie's prime motivation is always his life-long lust for Marge, which reaches its ultimate form in the Season 31 episode "Hail to the Teeth." Once again fabulously wealthy, he invites Marge and Homer to his lavish wedding (via hologram); at the ceremony, they are shocked to discover that Artie's "bride" is an exact robotic replica of Marge. The entire wedding was a sham in order to make Marge jealous and spur her nonexistent feelings for him.

One night after another fight with Marge, Homer finds himself in a hillbilly bar drinking a bottle of Fudd (the rural counterpart to Duff beer) when the bar's waitress Lurleen (Beverly D'Angelo) gets up on stage and sings a beautiful country song. Transfixed, Homer becomes her manager, much to the tooth-grinding chagrin of Marge. Caught between a bewitching chanteuse and his family, Homer does the right thing and comes home, leaving Lurleen to pine for him on the country-fried variety show "Ya Hoo."

That was Season 3's "Colonel Homer." Lurleen would pop up in the background every so often after that, most notably in Season 4's "Marge vs. the Monorail" (voiced by the late Doris Grau), but she and D'Angelo made their official return in Season 19 with "Papa Don't Leech." On the hook for $50,000 in back taxes, a destitute Lurleen goes to Homer and Marge for help. After listening to her songs of neglect, they try to reunite her with her deadbeat father — only for him to steal her songs and sell them to the Dixie Chicks (appearing as themselves). In the end, Lurleen has a new lease on life, and she and Marge have reconciled — up to a point.

The show's very first sequel, "Brother Can You Spare Two Dimes?" from Season 3 continues the story begun in Season 2's "Oh Brother, Where Art Thou?" After Grampa reveals that he had an illegitimate son who was given up for adoption, Homer tracks down his long-lost brother, wealthy Detroit automaker Herb Powell (Danny Devito). Herb welcomes his new family with open arms and even offers Homer a job designing a new car for the common man. When that car, called The Homer, turns out to be a hideous eyesore, Herb is left ruined.

A year later in "Brother Can You Spare Two Dimes?" Herb is a hobo living under a bridge, but still dreams of finding a million-dollar idea and getting back on top. When he sees that Homer has won a $2,000 award from the power plant (really a settlement for the plant making him sterile), Herb seeks out his brother and asks for the money as an investment in his latest idea, a translator that deciphers what babies mean when they coo and babble. Other than a quick voicemail cameo in the Season 24 episode "Changing of the Guardian," neither Herb nor Devito has been on the show since Season 3.

After years of "playing the buffoon" as Krusty the Clown's sidekick, "Sideshow" Bob Terwilliger (Kelsey Grammer) framed him for robbing the Kwik-E-Mart. Bob would have gotten away with it if not for Bart's belief in his hero's innocence and surprisingly keen powers of observation. And so began, with the penultimate episode of Season 1 "Krusty Gets Busted," the saga of Sideshow Bob and his murderous rage toward Bart, Krusty, Springfield, and society at large. Bob made his second appearance in Season 3's "Black Widower" as Selma's prison pen pal fiancé, but it was the third time around in Season 5's "Cape Feare" that the character evolved into his final form, complete with machete, "Die Bart Die" chest tattoo, and Bernard Herrmann-esque theme music.

Bob has made 22 appearances over the years, most recently in Season 31's Christmas episode "Bobby, It's Cold Outside," and worn many hats atop his comically large hair. He's been a Republican mayoral candidate, the actual mayor of a small Italian village, and a theme park Santa Claus. Most of the time, he's obsessed with murdering Bart, but every so often he has to save him, either from his brother Cecil (David Hyde Pierce) or from a rogue 1960s missile in Season 29's "Gone Boy." He has tried to kill Krusty on multiple occasions, though the two seemed to be on good terms in "Wedding for Disaster." Amazingly, nearly all of Bob's adventures (the "Treehouse of Horror" episodes excepted) fit together as a cohesive story: the tale of a cultured, respectable man whose insatiable bloodlust is just a heartbeat away at all times.