Achilles in His Tent

Sing, O goddess, the anger of Achilles son of Peleus, that brought countless ills upon the Achaeans. Many a brave soul did it send hurrying down to Hades....

—Opening lines to The Iliad, Trope Namer

A member of a team (often The Lancer) gets into a fight with everybody else and quits, vowing to never, ever return to the people whom they now hate so much. A threat then comes that is precisely suited to the missing member's talents. The other team members beg the quitter to come back, but with no success. The team head out without their ex-member, and are about to all be killed horribly.

Then the ex-member, seeing them about to die, realizes that he still cares about them after all. He leaps in with a Foe-Tossing Charge, saves everybody, and all are reconciled. An Aesop about friendship and teamwork ensues.

When done well, this is tied directly into the Story Arc. The bad guys know about the quitter, and send a specialized threat precisely because the quitter is missing. When done badly, the Monster of the Week just happens, by an amazing coincidence, to match the quitter's talents—and next episode, everybody will forget that the whole thing ever happened.

Sometimes, the quitter is a character who doesn't seem necessary or even desirable. The episode is thus about giving them some character development and showing both the audience and the characters why this person was on the team. Common with What Kind of Lame Power Is Heart, Anyway? characters, but has the danger of falling into a Plot Tailored to the Party.

This goes all the way back to Achilles sulking in his tent in Homer's Iliad (hence the trope name), making it Older Than Feudalism. Although notably, he wouldn't come out until his best friend / cousin (or just plain unrelated boy toy, depends on who you ask) was actually killed trying to take his place.

Contrast Ten-Minute Retirement, We Want Our Jerk Back. Often followed by a He's Back moment.

Compare with Just Fine Without You and Holding Out for a Hero. See also Changed My Mind, Kid. Heavily related to We Used to Be Friends.

See also Deus Exit Machina. A loose Good Counterpart is Dragon Their Feet. If the villain refuses to come out, it's Orcus on His Throne.

Examples of Achilles in His Tent include:

Anime and Manga

Mazinger Z: Kouji Kabuto did this -out of all people!- in episode 7. After mobs of people expressed his displeasure in having his hometown leveled by a Humongous Mecha battle by harassing him and after a quarrel with Sayaka, Kouji decided since nobody wanted him fighting, he would stay in home. Of course, it did not last long.
- Tetsuya also did it in the last episode of Great Mazinger. He was so jealous of Kouji he refused to sortie in Great Mazinger to help him when he was struggling.
Samurai Pizza Cats had an episode like this (No Talent Guido). Speedy and Polly get contracts for a singing career, leaving Guido feeling left out. The Monster of the Week attacks Little Tokyo while Speedy and Polly are recording a song. Guido refuses to fight, saying that maybe he had better things to do, too. Francine sends the rescue team to fight the monster. They do well until the Rude Noise engage them. Guido finally snaps out of it, when he sees the rescue team get blown away. Just as Speedy gets his ass kicked and Polly is reduced to Damsel in Distress Guido makes his grand entrance, dispatches the ninja crows in a cooly excecuted Foe-Tossing Charge and finishes off the monster in what is considered to be his Crowning Moment of Awesome. This also served to give Guido some actual Character Development, showing him grow from simply a Handsome Lech to a Jerk with a Heart of Gold.
This happened between Agumon and Masaru/Marcus in Digimon Savers. After they fell out, Masaru tried to fight alone. He managed to beat up some jerk ass baseball hooligans, but when the Monster of the Week shows up (a Black Garurumon) that's when he runs into trouble. Kutamon even lampshades this by saying how Geogreymon would have been perfect to battle him.
Shinji does this in Neon Genesis Evangelion, after his Eva is forced to try to kill one of his best friends. His return in the following episode becomes his Crowning Moment of Awesome.
- Subverted, as with damned near everything else in Evangelion, when Shinji gets his ass kicked anyways, and mommy has to come to the rescue again, in a scene which is oddly mirrored in reverse in the movie with Asuka.
  - It's not stated outright but based on Shinji's Sync Ratio shooting up to an 'impossible' 400%, plus the next episode revealing that Shinji's body has vanished and his soul has been absorbed by the Eva in essentially the same way as his mother's was, it seems it really was Shinji's will driving the Eva this time.
  - Way less debatable in Rebuild, where even Mari fails to take out Zeruel and Shinji pwns it himself by directly accessing Eva01s god-like powers without any berserk whatsoever.
Ken (also known as Mark) of Science Ninja Team Gatchaman / Battle of the Planets fame made a positive habit of quitting in a snit or going AWOL for his own reasons at the worst possible times.
An inversion of this trope happens in a sports shounen manga, Fight No Akatsuki (Akatsuki's Fight), in that the leave-taking is actually an admirable and sensible thing. Two best friends, Akatsuki and Kiyo, are on opposite teams. The coach of the Opposing Sports Team orders his players to injure Akatsuki so bad that he can't play anymore. Kiyo hurls a basketball at the jerk's head, says nuts to that, and sits the game out rather than be a part of that. After they fail to stop Akatsuki, Kiyo returns to the game to play against his best friend fairly.
Wu Fei spends an entire episode of Mobile Suit Gundam Wing doing this after failing to kill Treize; it takes words of encouragement from future Team Mom Sally, and the deaths of her mercenary friends, to snap him out of his funk.
One Piece had a somewhat subverted version of this trope play out over an entire two-year long story arc. Usopp protests when the crew decide to junk their broken-down old ship in favor of a shiny new one, as the ship had been given to them by his girl back home, and was practically one of the True Companions. Told to get over it by Luffy (in a rare scene where he actually issues an order as captain) Usopp chooses to leave the crew instead. Later, our heroes find themselves in huge trouble, so Usopp returns to help out, but, unwilling to face his former comrades, he shows up in an incredibly obvious disguise (which still manages to fool two of the more gullible crewmembers.) Despite helping save the day, he is still not asked back on the crew, (even though everyone really wanted him back) since he went against a direct order from his captain. Only when he apologizes without provocation (and, as it happened, does so very loudly) do our heroes welcome him back.
In Code Geass, Lelouch has a few moments like this after his various Trauma Conga Lines. The most unfortunately timed one is in R2 episode 19, where because he's in his chambers and not responding to calls after his most recent and crushing one, Schneizel is able to almost completely demolish Lelouch's already-tenuous credibility as Zero and reveal his secret identity and mind control power.
Sailor Mercury is prone to the more benevolent versions of the standard plot: Mercury, who starts as the only Senshi without offensive abilities, is too nice to storm off. Instead, she's offered a chance to study abroad and further her goals of becoming a doctor, which will remove her from the Senshi. She's about to take it, but changed her mind at the last moment so returns in time to get her mid-season power upgrade (which finally makes her more action-geared) and rescue the rest of the team from a monster only weak to ice, and she returns to the fold. Later in the season, she's attacked by a monster that causes paranoia and self doubt, and she hallucinates that everything everyone says to her is derisive and mean. Eventually, her faith that her friends would never say such horrible things allows her to break the spell and come back to everyone.
- Sailor Venus also has an episode where she decides to leave the Sailor Senshi. She isn't angry about it, but wants time off from saving the world so she can join the volley ball league she was forced to quit and get a boyfriend. Who shows up but a Heart Snatcher fused with a volleyball, making her volley ball skills invaluable as Sailor Venus in order to save her love interest. She then decides to go back to being a Sailor Senshi, possibly after learning that said love interest already has a girlfriend.
In Yu Yu Hakusho's Chapter Black Saga, Hiei, whose helping the heroes had until this point been reluctant, refuses to help them after hearing about the plan to open a portal to the Demon World, which would enable him, a B+ class demon to return there. He returns to help Yusuke against Kaname "Sniper" Hagiri, and is persuaded to help after being offered the Chapter Black tape.
Brad/Ballad in Zoids does this in one of the beginning episodes, refusing to fight the Backdraft Group because he won't get paid for it. Of course, he comes in at the last minute and saves everyone... because Dr. Toros offered him Bit's next few paychecks.
Saiyuki has one of these for every one of the Sanzo party apart from Goku (Hakkai's is anime only though) results in the rest of them going "fine see if we care" normally "we can manage just fine without...."
- When Goyjo stays behind to go after Kami-sama the others eventually go back, the reason they give is he's caused so much trouble they have to go beat him up. Which they do once they get there (arriving at just the right time) however Gojyo realises he needs them in a slight subversion, however it is him who manages to save all of them when the building starts falling down.
- In the anime Hakkai ignores all of the others for a while because he's waiting for them to apologize for not tidying up as they promised to (reload filler is odd sometimes) they say we're not apologizing we can manage with out him and try to (Hakkai does all the cooking and cleaning and has taken the credit card so...). he breaks when Goku can't stand it any more and comes and tells him how horrible it is and basically makes the other two apologize
- Sanzo's one lasts considerably longer than any other separation (they manage without him for longer, and he's more stubborn) he's gone off on his own private agenda for a bit.
- The only time they admit they can't manage without a member is when jeep goes missing (Hakkai says that its worse than when Gojyo left, causing the latter to object that he shouldn't place below a car)
So Ra No Wo To. Because of Parental Abandonment issues, Rio Kazumiya spends most of the series refusing her father requests to agree to an Arranged Marriage that could stop an ongoing war. She eventually yields to prevent further bloodshed.
A rare villainous version in Fresh Pretty Cure: when one of the Quirky Miniboss Squad pulls a Heel Face Turn and defects to the heroes, one of the remaining members tries to invoke this trope to bring her back. She turns him down every time, but he keeps trying right up until the end of the series because of the friendship they used to share.

Comic Books

The Fantastic Four was notorious for this happening, particularly with the Thing.
Again in Marvel, Namor was rejected by the Atlanteans and later he rejected them. It took the god Neptune giving Namor his trident to change Namor's mind.
Subverted in Justice League Elite by Major Disaster who suffers a breakdown after his Alcoholism gets a teammate killed. When the call comes for him to return he refuses in an attempt to stay away from the things that drove him to drink in the first place.
The Sentry from Marvel Comics tends to do this a lot. The main reason for this, of course, is that he is described as the worlds most powerful hero and in all probability could solve any problems of other heroes nigh instantly. In his first appearance in New Avengers, he effortlessly flies Carnage into space and rips him in half. When his evil counterpart the Void emerges, it takes the entire New Avengers, the X-men and the Fantastic Four just to hold it off long enough for the Sentry to beat it in a Battle in the Centre of the Mind.
In Judge Dredd, during the First Robot War, Dredd leaves the Justice Department when Goodman refuses to have all the robots in Mega-City One decommissioned. Sure enough, the robots rebel, but Dredd comes back by the end of his retirement strip.
In Batman: No Man's Land, Batman himself pulls this after he fails to stop Congress from condemning Gotham City. An encounter with Talia al Ghul gets him to shape up and return to Gotham three months later.

Film

Troy. "We stay until Agamemnon groans to have Achilles back!"
Star Wars - As soon as Han Solo gets the money for doing what he was hired to do, he jumps ship, claiming that he's Not in This For Your Revolution. Of course, even people who haven't seen the movie knows what happens next: "You're all clear, kid! Let's blow this thing and go home!"
- Then he does it again at the beginning of The Empire Strikes Back, though not directly onscreen. He also doesn't spend long ~~in his tent~~ running from bounty hunters before he discovers that Luke has gone missing and he pops back out again.
- And Luke gets in on the action by secluding himself through the entirety of The Force Awakens and most of The Last Jedi out of guilt from the actions of one of his students.
Parodied somewhat in Team America: World Police, where Gary is accused of this despite the fact that his abilities would have been obviously useless-- though, of course, they eventually do need an actor for the final mission.
Lancelot becomes a partially insane vagrant in the movie Excalibur who blames the king for bringing a pestilence upon the land. At the climatic battle, he returns to fight by the king's side.
Gambit in X Men Origins Wolverine.
A non-combat variant of this occurs in This Is Spinal Tap. Due to an increasing series of setbacks and personality conflicts, Nigel Tufnel stomps off in the middle of a show (which is going very badly), effectively quitting the band. The band's fortunes continue to get worse, as their venues and audiences get smaller, and they're forced to cut all of Nigel's songs (eliminating the bulk of their set). Finally, in the last ever performance of what's left of Spinal Tap, Nigel returns with an offer to reunite for a Japanese tour supporting their latest album. Rejected at first, he's invited back, as an expression of the Power of Rock/Power of Friendship.
Another non-combat version: Hardy Kruger's character in The Flight of the Phoenix.
Yet another non-combat version: In The Jungle Book Bagheera throws up his paws in desperation at Mowgli's continued rebellion, only to return when he gets in trouble again. He returns no less than three times: upon Mowgli's initial encounter with Baloo (which turns out to be a false alarm), when Mowgli gets kidnapped by monkeys, and when Mowgli runs away from Baloo.

Literature

Named for the famous incident in Homer's Iliad, which fits the formula almost perfectly, with an added touch. Agamemnon tries to coax Achilles back by meeting the demands he originally made before the new threat, but Achilles now refuses them. Also, in stark contrast to modern TV examples, Achilles does not learn An Aesop about teamwork or friendship. He re-enters battle out of pure blood rage, after his ~~best friend~~ cousin Patroclus kicks the bucket, and winds up forming an Odd Friendship with the enemy king instead of with Agamemnon.
The Achilles situation is exactly mirrored in the final book of the Percy Jackson and The Olympians series: Clarisse, daughter of Ares, refuses to let any of her siblings join the fight because they won a prize in battle that got taken away. Even after they get it back, she won't fight in the war. Eventually Clarisse's new best friend, Silena, daughter of Aphrodite, steals her armor, leads the rest of Ares's children into battle, and gets killed in the fight. Clarisse then rejoins the war, just like Achilles.
- Well, given that the entire series is a big Shout-Out to Greek Mythology, and just about every event is some modernized version of an ancient Greek myth, you knew this one had to turn up sooner or later. Percy even gets the same powers as Achilles in said book by bathing in the river Styx. And Achilles' shade makes an appearance to try to talk him out of it.
In Harry Potter and the Deathly Hallows, Ron temporarily storms out of the plot and returns just in time to save Harry from almost certain death.
The Star Wars Expanded Universe featured Garm Bel Iblis, a founder of the Rebellion who left when he felt it was risking becoming a dictatorship, feeling that replacing the Emperor with an Empress wouldn't be an improvement. After realizing his folly, he returns but refuses to take command of the fleet, even while they're being attacked, by an enemy commander that only he is skilled enough to match. He finally gives in after speaking with Mon Mothma.
Played with in Tad Williams' Otherland series. In a memorable sequence, the protagonists find themselves in a computer simulated version of the actual Trojan War, filling the shoes of many of that story's heroes. Orlando is Achilles, but in a subversion, the reason he can't come out to fight is because he's genuinely too ill. The NPCs still treat him according to the story line, though, forcing Sam (as Patroclus) to don Achilles' armor and confront Hector. In trying to rescue her, the protagonists inadvertently trigger the same sequence of events as in the story.
The entire premise of Atlas Shrugged is that the people really important to civilization decide that it's no longer their job to let their skills benefit if they themselves cannot also enjoy the fruits of their labor. Of course, here it's portrayed as the right thing to do.
An interesting inversion occurs in Aztec, where the protagonist, Mixtli, tends to leave the city and go wandering about whenever he suffers a Heroic BSOD, rather than stay at home. It has the same effect on his friends and companions, though.
In Septimus Heap, Septimus runs off from the Quarantine laid around the Palace in a fit of anger after having been excluded from the Quarantine Spell.
In Michael Flynn's Up Jim River, the Pedant does this. More than once.
Don Quixote: Being present in a lot of Chivalric Romance books (Amadis of Gaul, Beltenebros and Orlando did it), this trope is parodied by Don Quixote: When he is at the Sierra Morena forest, he invokes this trope by sending Sancho with a letter to Dulcinea (his imaginary love interest) explaining her that he will be in the forest until she forgives him… Even when don Quixote has not made anything against her. This madness will force the Curate and the Barber to ask Dorotea to pretend to be a princess and ask Don Quixote a favour to get him out of the forest.

"It seems to me," said Sancho, "that the knights who behaved in this way had provocation and cause for those follies and penances; but what cause has your worship for going mad? What lady has rejected you, or what evidence have you found to prove that the lady Dulcinea del Toboso has been trifling with Moor or Christian?"
"There is the point," replied Don Quixote, "and that is the beauty of this business of mine; no thanks to a knight-errant for going mad when he has cause; the thing is to turn crazy without any provocation, and let my lady know, if I do this in the dry, what I would do in the moist;

Live Action TV

A rare non-combat example: the 1980s children's puppet show Letter People. In an early episode, Miss A gets into a fight with the other letters and quits. Since Miss A was the only vowel in the cast at this point, nobody can form a word without her and they have to beg her to come back. (Since she was also the only female letter introduced at this point, this may have been a sly way to teach feminism to the target audience.)
In Angel, Wesley left, not entirely of his own volition (he was heavily injured), ~~after~~ during Season 3 and his mistake with Connor, followed by about a season of intermittent contact with the team, during which they sometimes sorely missed his talent. He just sort of drifted back in about mid-season 4 with the whole Cordy crisis.
The premiere of Buffy the Vampire Slayers second season. In "When She Was Bad" Buffy comes back from her summer in L.A. still steaming with issues from being killed for a minute in the Season One finale. When the Master's men steal the Master's bones with the intent to resurrect him, Buffy explodes at Giles and blows off the Scooby Gang's attempts at consoling her. This lasts until Willow, Giles, Cordelia, and Miss Calender are captured by the vampires for the resurrection ritual.
Also happened in an episode of Parker Lewis Can't Lose, involving Larry Kubiac and the football team.
Not quite an example, but certainly an honorable mention: In Star Trek: The Next Generation episode "Peak Performance", Data loses a game of strategy that he expected to win. Because of it, he loses confidence in his abilities and stays in his quarters, trying to determine what is wrong with his programming. Several crewmembers try to get him out of it and back on the bridge, one comparing his behavior to "sulking like Achilles in His Tent". He's convinced that he's not unreliable and takes his place on the bridge in time to assist in a sudden crisis and formulate the plan to save the crew.
In Robin Hood: Robin overpowers Guy and ties him to a tree after realizing that he is man behind the attempted assassination of King Richard. He gets so wound up that he nearly resorts to torture and refuses to listen to his men who feel that it's more important to stage a rescue mission to save a fellow team-mate that's been captured. After several failed attempts, during which Robin just sits under a tree, the outlaws return unvictorious and it takes Marian to snap Robin out of it and suggest a hostage trade.
In season 5 of Babylon 5, Garibaldi is assigned to monitor intelligence reports and coordinate the peacekeeping forces to prevent a war from flaring up. While he's busy drowing his sorrows, the war escalates and the peacekeeping forces are unable to regain control before Centauri Prime is bombarded from orbit.
In Between the Lions, Click (the computer mouse) is jealous of Lionel and Leona making a fanclub for the little brown mouse (in the Lion and the Mouse), due to them thinking of her (the mouse) as a hero, and decides to leave. But then she finds out that Cleo is in a trap in the book and needs to be rescued, and returns.
Happens in Glee in the episode Sectionals, when Finn abandons New Directions after learning that Quinn's baby isn't his and that the rest of the club had helped her to keep the secret. Naturally, he shows up to sectionals right after their two competitors finish performing (all of New Directions' intended songs) with new pieces prepared and ready to go.
In the episode "The Late Captain Pierce" of Mash, Hawkeye is declared deceased by the army. Tired of the war, and tired of getting the decision to be reversed, he takes off with the ambulance that's there to collect his body, just when new casualties arrive. After the ambulance leaves the camp, it stops, and Hawkeye walks back to the 4077.

Professional Wrestling

This trope pretty much defines Sting's character in WCW through the entire year of 1997. Hell, we might as well call this trope Sting In The Rafters.

Video Games

Falco from Star FOX did this in Adventures, and in one of the endings in Command.
Susano, the Fake Ultimate Hero of Okami, does this when he finally admits, to the villagers and himself, that the Orochi of legend was real and he has released it. It takes his girlfriend, Kushi, to shake him out of it, and even then she is nearly eaten by Orochi herself.
Shinon did this in Fire Emblem Path of Radiance after Greil died and Ike became leader of the mercenaries.
A small use happens early in Golden Sun. After the guy capable of removing large overgrowth blocking the way leaves the group to pursue his own mission he comes back, having quickly hit a dead end, right after the main group finds their path impeeded by such overgrowth.

Webcomics

In The Order of the Stick, Roy decides not to help the rest of the team rescue Elan, because Elan is too useless to be worth the risk. He changes his mind the following night, after he realizes how much of an asshole he's being.
- More that he realizes he is being untrue to himself by abandoning Elan - his whole reason for becoming a fighter and an adventurer was to help others. When Roy dies (he gets better), he learns that had he not gone back, he'd have ended up in a rather worse afterlife.
Referenced in one Penny Arcade comic in which Gabe asks his Guildmaster permission to try a different MMO. The Guildmaster's response is to purposefully do something that requires Gabe's character.
- "But...that is suicide!" "Is it, druid? I call it murder."

Western Animation

One of the very first Thomas the Tank Engine episodes written featured Henry trying this in "The Sad Story of Henry". In this case the episode ended with Henry being locked in the "tent" he sulks in for "Always and Always and Always." and it wasn't until the following episode that Henry got to make up for his wrong-doings and save the day.
- In "Trouble in the Shed" Henry tries it again, along with Gordon and James and once again, it backfires. The Fat Controller shuts them up and gets Thomas and Edward to run the line.
Kim Possible: Ron quits when he thinks Kim is jealous of his new success at Bueno Nacho. Kim thinks she can do without the goofy sidekick, but it turns out he's vital. Him or his naked mole rat?.
Teen Titans: Cyborg quits after a fight with Robin, then returns just in time to save everybody with the Foe-Tossing Charge.
A couple of times in Theodore Tugboat. In Guysborough's Garbage the eponymous Guysborough refuses to collect garbage, resulting in the Big Harbour becoming a big mess. A visiting ship, to whom cleanliness is Serious Business insists on leaving the harbour.
- There was also one time when Hank, feeling that no one respected him because of his short name, changed his name to Henry. After a big mix up, a large barge goes out of control and speeds through the harbour. Hank is the only one fast enough to catch the barge but he ignores their pleas for help until Theodore addresses him as Henry.
WITCH: Cornelia quits when the team fails to protect her best friend, Elyon Brown, from the bad guys. Without the full team, everybody else's powers are weakened (which strangely didn't happen the last time the girls had to send a partial team), and new monsters attack who Cornelia's powers would have been perfect for. She inevitably snaps out of her funk in time to save everybody. This turned out to be a turning point, giving Cornelia real Character Development for the first time.
In an episode of Recess, Gus refuses to take sides in a dodgeball fight, despite being a dodgeball virtuoso at one of his older schools. Upon seeing a younger student getting clobbered, however, he enters rage mode and proceeds to wipe out the opposing team single-handedly.
A variation of this is shown in Beast Wars, where Tigatron does this after he accidentally kills (a non-Transformer) ~~tiger friend~~ his mate in a firefight, and only returns after he realizes the bad guys aren't going to stop destroying if he does nothing. Somewhat unique in the fact that the teammate that attempts to coerce him back into the fray is a battle-hungry warrior who attempts to strong-arm him under threat of death, which certainly didn't help matters any.
Captain Planet had at least two episodes with Ma-Ti angsting, trying to quit the team and having to come back to save the day. Hell, Kwame tried to quit once in the middle of an Heroic BSOD, and he was the de facto leader of the team. There was also a two-parter episode where Wheeler tries to change history so that he never became a Planeteer, only to travel forward in time and discover the world was destroyed by global warming because everyone was DOOMED without him.
This happened to The Tick in "The Tick Vs. Arthur's Bank Account". Handy the Hand Puppet even points out the allusion.

Handy: Even now he sulks like Achilles in His Tent! (beat) Achilles? The Iliad? It's Homer?! Read a book!

Teenage Mutant Ninja Turtles used this trope more than once, with more than one turtle.
- The entire TMNT movie could be a variation on this theme. Leonardo has stayed in South America for a year after his training was supposed to be over. While he's gone, Raphael develops some serious anger issues with his older brother, and sort of does the inverted Achilles in His Tent as the team falls apart: he goes out and fights crime solo as the Nightwatcher while his two younger brothers work menial jobs, watch television, and play video games. When Leo comes back, Raph is way too angry to reconcile with him, and keeps up his Nightwatcher act until Leo - literally - "unmasks" him. Leo and Raph duel, and Raph almost wins, but backs off when he realizes he's become angry enough to actually hurt (kill?) his own brother. As Raphael runs away, he hears Leo scream as the Big Bad and his Five-Bad Band capture him. He tries to go after Leo, but the bad guys get away. Raphael returns home, where Splinter gives him some Epiphany Therapy, after which he leads the other turtles (with some help) to storm the bad guys' tower and rescue Leo.
The Simpsons had an episode where Marge buys an SUV, gets road rage, and has her license revoked. The next day, Homer's idiocy causes a breakout of rhinos at the zoo. Chief Wiggum immediately comes crawling back begging her to put her anger to good use, but Marge stubbornly refuses. That is until she looks at the TV and sees her family surrounded.
Family Guy lampooned this with the exterminators in season 2 ep 17. One of them, named Logan, is having an emotional breakdown because his family was carried off by fire ants. But he shows up just in time to save his fellow exterminators from a flea infestation. Please note that instead of being "exterminators" with insecticides, they're basically a bunch of soldiers with guns and body armor.
The Powerpuff Girls does this in one episode. Bubbles gets humongous glasses and is teased by her sisters until she flies away, sobbing. Turns out that they need to her to fight a giant ant, and while Blossom and Buttercup's heat vision isn't strong enough, Bubbles' sure is when it's magnified 10 fold by her glasses, killing the monster and saving the day.
The Return of Jafar has Iago attempt to fly off after breaking the good guys out of prison but before the final confrontation with Jafar.... only to fly back in later and save the day, with a resounding cry of, "HEY, JAFAR! SHUT UP!!!"
In one episode of Totally Spies!, Alex quits WOOHP, and is replaced by Britney. The former returns to action when the latter and the other spies are captured.

Real Life

Some people on message boards do this in an attempt to prove how indispensable they are. You've probably come more than a few of those "Leaving the fandom, back in five minutes!" types.
- Jared Ornstead in particular is infamous in Anime Fan Fiction circles for his frequent "permanent" departures from the Net due to "persecution" from a (possibly mythical) group of haters.
- And then there are people who fake their deaths and return as (often badly disguised) Sock Puppets to grieve and pile on the "posthumous" praise.