The hero has accomplished their goal; they've killed the Big Bad, or defeated them forever, or at least scored a major blow against the antagonist. They've done what they set out to do...
...but not so fast! It turns out that by the very act of success, they've unwittingly made things worse. Maybe the now-dead antagonist was actually holding back an even greater evil. Maybe the villain, having been defeated or damaged, is now transformed into a new, ultimate, unstoppable, invincible, angry form, often against the villain's will. Maybe the villain, despite their villainy, was serving some other greater good — keeping the world/universe/nature/whatever politically or literally balanced — and their demise throws things into chaos. Maybe the so-called villain was actually a Hero Antagonist, and you just unwittingly handed a huge victory to the real villain. Maybe that princess you saved is a cold-hearted tyrant at the head of an oppressive regime, or even a Sealed Evil in a Can. Perhaps taking down the villain has resulted in an Evil Power Vacuum, and now even worse guys are fighting to fill the void that the previous villain left, causing even more havoc than that previous villain could have ever dreamed. Or perhaps the only means of foiling the villain involves questionably massive "collateral damage" and is so extreme that the hero is now the worst example of He Who Fights Monsters, My God, What Have I Done?, or Full-Circle Revolution. For whatever reason, the hero's victory over death and destruction directly or indirectly leads to an even greater wave of death and destruction, or something else that puts a Downer Ending spin on everything. Oh dear.
Maybe the villain themselves will warn the hero about the possible consequences, as a last-ditch attempt to save their own skin, or as a bitter "parting shot" to ruin the hero's victory ("You fools... do you even know what you've done?"). Villains being villains, this may just be a bluff. Or maybe the villain will just lament over how the hero defeated them despite all their efforts - it wasn't some sort of plan of theirs for the hero to "win" and thus make things worse (if it was, that'd be My Death Is Just the Beginning). Then again, Poor Communication Kills often comes into play as the villain will usually be uselessly vague and give no concrete reason for why foiling him would be bad. On the other other hand, a clear warning might be taken as Cassandra Truth anyway. You can't win.
If the mission was a rescue, it was an Unwanted Rescue, and the former captive may bitterly inform them of the true facts.
In most cases, of course, the hero will take full responsibility for their actions and be haunted by them, horribly traumatized. Now their new mission is to stop the new danger they've unleashed, preferably in a way that doesn't spawn ever greater menaces. Darker plotlines may end the story right there instead, and it's always possible the villain's demise inadvertently resulted in the irreversible destruction or horrifying mutation of the world. If used excessively, this trope often leaves an audience with a sense that the hero shouldn't have tried to change things for the better and indeed shouldn't have even left home. Can also be a moral about getting seriously involved in things without learning much about them.
This trope can be annoying in video games as often-times Stupidity Is the Only Option, particularly in the case of a MacGuffin Delivery Service... It is not particularly fair to try to make the player feel guilty about a course of action they had no control over, and indeed, might've gotten a "Game Over" if they attempted to not fulfill the objectives in question.
The term "Pyrrhic Victory" has the same connotation and originated from the Pyrrhic War fought by King Pyrrhus in 279 BC, which makes "Nice Job Breaking It, Hero" Older Than Feudalism. The tropes overlap, but Pyrrhic Victory is when someone succeeds at their goal with a very high price, while Nice Job Breaking It, Hero includes actions that might not be necessary or even intentional. In addition, this trope sometimes results in no victory at all, not even a Pyrrhic one.
Sometimes a badly thought-out plot for the sake of action has exactly the same effect when Fridge Logic catches its tail. That's one of the reasons why a good Game Master habit is writing the plot starting from the "what happens if Player Characters aren't here at all or do nothing" point.
This trope is a common problem with the Small Steps Hero. Compare Create Your Own Villain, What the Hell, Hero?, Unwitting Pawn, Must Make Amends, You Already Changed the Past, Two Rights Make a Wrong, Nice Job Fixing It, Villain (but note that villains are also subject to this trope — they can do something careless that screws them over or helps out a worse villain). Compare We Want Our Jerk Back! when the hero/villain makes the villain/hero powerless, only to have it backfire and give them a worse villain/hero/fate than expected, resulting in them wanting things to go back the way they were. Better the Devil You Know is a similar situation, where the utter defeat of one villain can lead to a completely different and greater evil taking over. This trope may lead to a Redemption Quest in an attempt to make up for the mistake. Has very little to do with Nice Job Breaking It, Herod (in fact, that one usually leads to the biggest cases of the complete opposite Trope.)
Hitler's Time Travel Exemption Act, in certain cases, is a Sub-Trope of this. See also Had to Come to Prison to Be a Crook, which is this as applied to a legal system. (Or at least a well-intentioned one.) May overlap with Self-Fulfilling Prophecy. No Endor Holocaust is what happens when this is ineptly averted. And if the hero dies following the reveal and is unable to stop the new menace, you've just read a Shoot the Shaggy Dog story. Despite obvious parallels, most Load-Bearing Boss in video games do not fall under this category. When this happens with fandoms, it's Why Fandom Can't Have Nice Things. Pacifism Backfire is "Nice Job Sparing Him, Hero". Compare Tragic Mistake.
It frequently overlaps with No Good Deed Goes Unpunished.
No real-life examples are allowed (Truth in Television as it is), and for that, you have no one to blame but yourselves.
This trope usually involves a plot twist, so beware of unmarked spoilers!
Example subpages:
- Anime & Manga
- Comic Books
- Fan Works
- Films — Animation
- Films — Live-Action
- Literature
- Live-Action TV
- Pro Wrestling
- Tabletop Games
- Theatre
- Video Games
- Visual Novels
- Webcomics
- Web Original
- Web Videos
- Western Animation
Other examples:
- Happy Heroes: In Season 2 episode 11, Happy S. enlarges the sun with the magnifying glass to melt the ice monster. It works well to melt the monster, obviously, but then there's the matter of Happy S. having made the sun big enough to make it dangerously hot on planet Xing Xing... oops.
- In episode 1 of Pleasant Goat and Big Big Wolf: Marching to the New Wonderland, the goats use their new trains to fight Wolffy in his Celestial Wolf train. Tibbie manages to break the gun on the Celestial Wolf, keeping Wolffy from shooting at them and giving the goats the perfect chance to attack... and then Sparky repairs that gun, not realizing that his train is the repair train. Cue Wolffy quickly using the opportunity to attack the goats with his shrinking powder.
- In the Big Finish Doctor Who drama The Lights of Skaro, as Benny finds herself wandering through the ghosts of Dalek history, she meets a group of early Daleks who were going to destroy the last few Thals and then rest, content that - as there was no life on other planets - they were alone in the universe. Then the stranger came and helped the Thals defeat them. Suddenly, they knew there was life on other planets, some of it could time travel, and it was all as bad as the Thals. Great job, Doctor!
- Halo 2 ARG I Love Bees ends with the gang taking out a Forerunner artifact and uncovering an evil plot by a power-hungry man in the Office of Naval Intelligence, only to inadvertently call the Covenant to Earth, triggering the invasion at the beginning of Halo 2note .
- In Zaltec II: The Generation Stone, when you find the titular Stone, you end up changing a past event which results in the establishment of a cruel totalitarian kingdom.
- In the second Album of The Protomen, Dr. Light and Joe attack the city that Dr. Wily has nearly taken control over. However, after destroying one Transmitter that Wily has used to control the robots, with Joe being killed in the ensuing blast, Light realizes that there is a second Transmitter, and the attack is exactly what Wily needed in order to declare Martial Law on the city and take complete control.
- Paul McCartney decided that the best way to revitalize The Beatles was to get the band back to its roots by recording a live album and putting on a concert. It did not work out.
- From David Bowie's "Cat People": "I've been putting out the fire with GASOLINE!!!"
- Classical Mythology:
- Pandora opened a box which should not be opened and released pain and sickness into the world.
- Prometheus stole fire and give it to the humans. After receiving fire, the humans began to make sacrifices to the gods in thanks. They burned up lots of great-smelling food, which the gods found pleasing, and calmed Zeus' anger. Prometheus, upset at seeing his creations burning up the best parts of their food, decided to change this. He ordered the humans to butcher a cow and split it into two piles: one was all the steaks, ribs, etc. (the good eating parts) covered in bones and sinew. The other pile was all the organs and viscera covered in "snow-white fat". Prometheus then asked Zeus to come down and pick for himself which pile he wanted for his daily sacrifice. Zeus, being powerful but not terribly smart, picks the better-looking pile, and ends up the fool, which reignited his rage. Essentially, Prometheus wasn't punished for stealing fire, he was punished for cheating the gods.
- Odysseus arranges for his rival Palamedes' death (both for Palamedes threatening Odysseus' newborn and for showing up Odysseus once), either by trickery or by murder. Palamedes' father Nauplius goes to the siege of Troy to ask for justice, but is denied. In revenge, Nauplius goes home but drops by the homes of the Greek kings, informing their wives that their husbands will bring home a number of Trojan women as concubines, leading to the wives independently plotting their husbands' murder. Chief among them is Agamemnon's wife Clytemnestra, whose murder of her husbands sparks yet another Cycle of Revenge involving her children.
- The Bible:
- Adam and Eve, who ate the Forbidden Fruit from the Tree of Knowledge which resulted in sin entering the world.
- Thanks to the economic policies Joseph put in place to take advantage of his prophetic dreams, a future Pharaoh will enslave virtually the entire known world, including his own people.
- Norse Mythology: Fenrir was originally beloved by all, since he was basically a cute wolf puppy. Over time, however, he grew large and fierce, until only Tyr dared to approach him, and one of Odin's visions foretold he was one of the monsters destined to end the world. Eventually the gods decide to chain him, and Fenrir swears revenge. It is ambiguous, though, whether or not he would have become evil anyway.
- During the development of Atari's Superman pinball, Steve Ritchie and Eugene Jarvis figured out how to use a guitar echo chamber to make a continuous background sound that intensified with the game action. For some reason, Atari management nixed the idea; Ritchie ended up using it on his next pinball, the top-selling Flash from Williams Electronics.
- The Black Tapes: The second season ends on the reveal that the Axis Mundi, the place where a five part symphony had to be played to usher in the apocalypse, is not Mount Ararat, as originally suspected, but the Pacific Northwest Stories studio itself, and that the show has been playing that symphony on the show on the show via the Unsound and the other audio files Alex and Nic thought had been coming from someone they knew.
- Dark Dice: In the final battle of season 1, Iaus Innskeep kills a bone devil, kicking its body into an abyss, which provides the last blood sacrifice needed to release the Nameless God.
- Sequinox: In the Gemini arc, the girls are sent to a Bad Future dimension and later find out it became that way because they were too good at defeating their Starter Villain Scorpio. The Night Queen responded by launching a full scale invasion of Earth, desolating the girls' home town just by touching it, and sending out hordes of stars and foot soldiers to wipe out humanity.
- Interstitial: Actual Play: Criss' plan to defeat the Smoke Monster is to use his magic to portal away the plug that keeps the island's magic contained. It brings the Smoke Monster down to normal, but also causes the island to begin to self-destruct.
- Revealed in the Sequinox prequel comic that Caiden hitting Tellie with his car ended up causing its amnesia and preventing it from giving the Sequinox girls important information on their destiny.
- The Adventure Zone: Balance Arc: It turns out that our heroes were directly responsible for the creation of three of the seven Grand Relics that have been causing untold chaos and destruction. Also, Lucretia, in an attempt to fix the problem, wiped the memories of the tres horny boys, Lup, Barry Bluejeans, and Davenport. All this to prevent the Hunger from finding and devouring the Light of Creation.
- The Magnus Archives: Jon destroys a table that he believes gives life to a monster that has been terrorizing him and his friends. After he breaks the table, he learns the table was actually keeping it contained, and that he's made it much more powerful than before.
- Within the Wires: In the Black Box season, the pilot's efforts to see his wife and child end up causing an IID raid on their commune.
- A radio station several years ago held a "Hold your 'wee' for a Wii", challenging listeners to hold their pee in as long as they could for a change to win a Wii game. A woman took the challenge and subsequently died of water intoxication.
- Dawn of a New Age: Oldport Blues:
- When Michal panics and accidentally sets himself on fire, Edward attempts to put him out by creating a fireproof clone to smother him. Not only is said clone not actually fireproof, but its attempt to grab Michal also breaks Ciro's attention, which dispels the barrier that Ciro had put around Michal to extinguish the flame's oxygen supply.
- From the same incident, Simon attempts to use his own superpower to absorb the flames. However, his attempt at doing so only freaks Michal out and causes his flames to intensify even more.
- During the final exams, Harriet gets into an altercation with Daigo. Ivan covertly uses his fate manipulation power to calm down Daigo and make him leave. However, this leads to Daigo assuming that Harriet had messed with his head, which then leads him to confront her again later, and that leads to Carlie and Devin getting seriously injured in the ensuing scuffle.
- In We Are All Pokémon Trainers:
- DS unknowingly made a few comments that inspired the Impossible Thief Emolga to steal Tagg's cynical side. As a result, Nihilist!Tagg was unleashed, and some of the trainers had to fight for their lives while DS went off to find the Emolga and get Tagg's cynical side back so he could be returned to normal.
- Tagg ends up starting the Keystone arc by taking Annoski's Keystone to the spot it needs to be for him to revive.
- During PMD-B Tagg's group allowing the last two Super Mutants to get away doomed Necropolis by having the Master send his army to destroy the place in reprisal.
- In Yu-Gi-Oh! East Academy, we have a subtle example from Marcus during his Tag Duel with Denero. While his strategy is solid, it unfortunately has the unforeseen consequence of being indirectly responsible for Denero merging his mind with the Meteor and becoming more aggressive and unstable as a result.
- In Fast & Furious: Supercharged at Universal Studios, after the protagonists dedicate a large amount of time telling the riders to shut off their cell phones in order to avoid their location getting traced by the ride's main villain, it turns out that Roman forgot to turn off his cellphone, a goof that launches the ride's main conflict.
- The whole goal of the heroes in BIONICLE is to awaken the sleeping Great Spirit Mata Nui. Unfortunately, Makuta (who put Mata Nui to sleep in the first place) plays them all for Unwitting Pawns: he allows the heroes to succeed and during a window of opportunity in the revival commits Grand Theft Me, taking control of the body of a Physical God and therefore also the world's very laws of nature. Nice Job Waking It, Heroes.
- Dreamscape: In Dylan's attempt to foil the Overlord of Evil's plan in the flashback in "Over and Under", he just makes things worse. And in the third flashback in "The Mystery of Melinda", Dylan accidentally spills the beans to Betty about her sister Melinda, which was the key to breaking her seal.
- At the end of Ducktalez 3, Vegeta is defeated by being thrown into the sun, which explodes the sun and covers the world in eternal darkness. Nobody seems to mind though. Every Ducktalez since then takes place at night.
- In Dusk's Dawn Star Whistle caused a storm that ravaged Ponyville.
- In Happy Tree Friends, Splendid appears to be incapable of not doing this.
- Hunter: The Parenting.
- There's a double-barrelled example in the second episode. Marckus and Door decided it would be a good idea to force their captured vampires into a death match For Science!... which leads to Pyotr diablerizing the other two and escaping. They don't know about diablerizing, because Big D keeps most information about vampires to himself because he's too concerned his sons will be Killed to Uphold the Masquerade.
- In the fifth audiolog, Marckus taunts Brock during their drinking contest about how he got the bartender (who also hates Brock) to give him non-alcoholic cider. Brock immediately sobers up out of pure rage, cue bar fight.
- Tlaloc's death in No Evil. Prior to the series beginning, there was the Tezcatlipoca Mirror, which was created to embody the concepts of Justice, Mercy, Freedom and Peace, and unify the world. Sadly, it became an Apple of Discord, with people fighting over who had the most right to it. To shatter it, the spirit Tlaloc traded his life, hoping to end the division. Unfortunately, it turned out that the pieces of the mirror were very driven to express the concepts they embodied, which led to the "Peace" portion, the Black Tezcatlipoca, becoming a horrible ooze that sucked the life from everything it touched.
- Puffin Forest: In the video "We Were Just Making Everything Worse," the players have a Heel Realization when they think about all the things they accomplished in the campaign and realized that they had unintentionally caused several disasters. They caused the sinking of a ship they were trying to save, killed a zombie who was actually trying to help them and came back for revenge, and helped a villain obtain the means to cause the apocalypse by being too trusting.
- Team Service Announcement:
- In Ranged Combat, just as the RED Sniper Jarated the BLU Spy, his Heavy, Soldier and Scout teammates all pose as snipers, confusing and scaring off said BLU Spy. Then when the Sniper tried to get a clean kill off the running Spy, his focus got broken by the teammates trying to shoot the Spy with their short range weapons, allowing the Spy to run free. That really pissed the Sniper off.
- In Subtlety, the BLU Spy is about to land a backstab on the RED Heavy... only for the BLU Scout to rush forward and start whacking the Heavy with a frying pan. The Heavy is not pleased, and neither was the Spy.
- Universe Falls: The Series: At the end of episode 6, Peridot announces that she's taken the liberty of fixing the "damaged warp pad" she found in the basement... meaning she somehow reassembled and reactivated the Dimensional Portal. Cut to Soos and Melody lost in another dimension with a creepy but affable skull-monster who communicates in gibberish.