"A common mistake people make when trying to design something completely foolproof is to underestimate the ingenuity of complete fools."
Whether it's The Ditz
, The Fool
, Inspector Oblivious
, or a monkey
, this miscreant is capable of derailing the most ironclad plan
by unknowingly taking a third option
. They ruin the implausible Gambit Roulettes
by exploiting their one, intrinsic flaw:
their reliance on Contrived Coincidences
, rigid patterns
, and the assumption that nobody would be stupid enough to actually push the Big Red Button
or fight the apparently unstoppable
How can they outdo the master at his own game
with nothing but stupidity and clumsiness? It's precisely because
these characters are the fools
of fate that they are uniquely placed to derail these schemes with the gentleness of a butterfly flapping its wings...of doom!
Put another way, they are an author's walking deconstruction
or Lampshade Hanging
of the Theory of Narrative Causality
: just as easily as a plot can come together it can be pulled apart with the tiniest, most ridiculous things.
When the character ruins the protagonists' plans by unknowingly doing something small but crucial, he becomes an Unwitting Instigator of Doom
. When the Spanner can trigger a series of coincidences, it's Disaster Dominoes
. When the plan is screwed and the character is also aware that he will screw the plan, and doesn't care, he becomes a Leeroy Jenkins
. Occasionally, may be Mistaken for Badass
. If the focus isn't on them, they're often an Unknown Character
Compare It Began with a Twist of Fate
, Nice Job Fixing It, Villain
, Outside-Context Villain
, Remembered Too Late
Opposite of the Unwitting Pawn
, often is
the Unwitting Pawn
until the final crucial moment. This is the main cause of Didn't See That Coming
, this trope being the "that". Inverse of Unintentional Backup Plan
, where a character accidentally completes an imperfect plan that would have otherwise failed. Compare with Out-Gambitted
, where someone's plan is successful but ineffective against a better-thought-out plan. Compare Too Dumb to Fool
, where the character is too stupid even to be baffled by explanations. Also, compare Evil Cannot Comprehend Good
, where the flaw is that the villain can't see someone being generous or brave or honest enough to foul up his plan.
Specialty of The Fool
. See also Didn't See That Coming
, The Dog Bites Back
, Who's Laughing Now?
The trope is reputedly named for the Industrial Revolution
-era practice of disgruntled workers throwing a spanner into a machine, either because of fears machines would put them out of work
, or as a bargaining chip for better working conditions (and often because they were the only ones who knew how to repair the machines as well).
(Note for Americans reading this: "Spanner" is the Queen's English word for what you would call a "wrench", with the added benefit of it being slang for a stupid person. The equivalent American phrase specifically involves a monkey
wrench, known in the UK as a gas grip — "He really threw a monkey wrench into my plan.")
Disgruntled French workers did this by throwing sabots
(wooden-soled clogs) into machinery - giving us the word sabotage
Often an ending trope, spoilers may be ahead.
open/close all folders
Anime and Manga
- A fairly common stock superhero plot consists of bad guys managing to finally defeat or capture the heroes, only to have the entire plan foiled by the appearance of an unexpected new recruit.
- Justice League of America #4: The villain Xandor traps the Justice League in an unbreakable diamond, but is thwarted by the arrival of Green Arrow.
- The Avengers #52: The Grim Reaper traps the Avengers in a death-like state with plans to finish them off permanently, until he is surprised and defeated by the newest Avenger; Black Panther.
- As an homage to the above-mentioned Justice League story, Grant Morrison's JLA run had a two-part story where Connor Hawke (the second Green Arrow) is forced to rescue the team after they are ambushed and incapacitated by the Key.
- In another Justice League story penned by Morrison, Prometheus's debut involved him taking down each member of the League with remarkable ease, having planned out their encounter to the letter. He hadn't planned that Catwoman would've snuck on board the Watchtower disguised as one of the reporters there for the day, and while he's trying to blackmail Superman into committing suicide on national television, she foils his entire plan by giving him a bullwhip to the nads.
- In The Transformers IDW series, Shockwave, planning to seed dozens of worlds with super energon so Cybertron wouldn't be mined hollow and die, is attacked by the Dynobots looking for revenge.
- It seems that for super-logical Shockwave Dinobots are his natural enemy - the first time when they were created (for the sole purpose of stopping Shockwave from getting to the crashed Ark) he completely dominated them in battle, thrown them down the cliff and started shooting at them from higher ground knowing that they can't even fight back but he overlook the possibility that someone may be stupid enough to attack the cliff itself bringing down the enemy standing on top of it but being buried underneath even deeper and faster than he was.
- In a strange way this is the hat of Fantastic Four villain the Mad Thinker - he creates amazingly complex, unassailable plans at the drop of a hat, accounting for every possible action of his opponents. But, every time, there is some random variable (what he calls the "x-factor") that doesn't take into account and buggers up his calculations. Marvel Adventures Spider-Man once established that the Thinker hates Spider-Man because his precognitive Spider-Sense makes him the one person on Earth who can effortlessly derail the Thinker's schemes without even deliberately trying.
- Zayne Carrick in Knights of the Old Republic basically sets in motion the Self-Fulfilling Prophecy of the Jedi — the one that they were trying to escape by killing their Padawans — when he (unintentionally) misses the knighting ceremony and then escapes. He continues to thwart their plans, intentionally or not, ever since.
- He also thwarts Arkoh Adasca's plan (with the help of Lucien and Alek) by tricking the Mandalorian leader into thinking Adasca is working with the Republic to trap him, which results in a three way brawl which culminates in Adasca's ship getting eaten by giant space slugs.
- Runaways often sees villains' perfect plans ripped to shreds by Badass Normal Chase Stein, who claims to be street smart but as a fellow teammate inquired, "What street? Sesame?"
- In The DCU, the Challengers of the Unknown are a team of adventure-seekers who miraculously survived a terrible plane crash, and therefore decided that they would willingly face any danger because, as they always put it, they were living on "borrowed time." It has recently been revealed that this is literally true: because they did not die on their appointed death date, the Challengers are the only people in the world whose fates are not recorded in the Book of Destiny. They can freely disrupt predestined events that would otherwise be literally inevitable, making them the ultimate example of this trope.
- Subverted in the Dan Dare series Reign of the Robots, wherein the only person that the Mekon paralyses after capturing the group is Dare's bumbling aide Digby, on the grounds that "he has no brain, therefore there is no predicting his actions".
- Groo The Wanderer: One of his more memorable derailings involved him going up against a mind-reading sorcerer. Groo fights his way to the sorcerer's throneroom, is confronted confidently by him... followed by a full page of the sorcerer making strange faces at Groo while the latter stared at him in befuddlement until he finally screamed "There's no mind to read!" and ran away.
- In Cerebus the Aardvark, the title character possesses a "magnifier" quality that influences everything and everyone around him to varying degrees. This causes the plans of everyone who tries to do anything that directly involves Cerebus to succeed wildly then crash spectacularly.
- Deadpool is frequently seen as such a rogue element that the guy who can copy someone's fighting style completely (Taskmaster) was still surprised by him.
- In Cable & Deadpool #50 (the final issue of the series) the Savage Land mutate Brainchild is countering the moves of every other hero in their attack on his base, but none of his predictions of where Deadpool is are accurate; turns out DP took the "Super Mario strategy" and went through the sewer pipes.
- Cyclops in the Ultimate X-Men arc Return of the King. Let us recap the situation so far. Magneto has regained his memories and is going on a rampage across the world with his acolytes while he waits for Forge to get his Doomsday Weapon ready. All the X-Men are either captured, killed, or on the run and still have no idea where Magneto's base is. It looks like all hope is lost, when Cyclops, who everyone thought was killed by Wolverine a few issues ago, is taken into Magneto's base as an injured mutant in need of healing. After recovering Cyke busts his way out and clues the other X-Men in on where the base is. All of this leads to a truly epic smackdown against Magneto and saving the world.
- In one week-long FoxTrot series, Jason finds it impossible to beat one guardian monster in a video game, as it instantly squashes his character every time he tries. Paige, who almost never plays video games, takes the controller and gets by the guardian by simply walking around him.
- Reggie Mantle tends to be this purely for the sake of being a dick in the Archie Comics. Most of the time.
- Snively describes Sonic as this in the Archie Comics' 200th issue after the blue blur defeats Eggman yet again, causing the doctor to go mad.
Snively: Eccentrics aside, he really is a genius. He can build the most amazing things and plot a hundred steps ahead ... And then there's you. All the building, calculating, and planning in the world couldn't beat you.
- Snively's not the only one who's noticed this. Mammoth Mogul has told Sonic that he will not attempt to conquer the world while Sonic's alive. Eggman reasoned himself to a degree of sanity after he realized this, thinking that Sonic's near constant exposure to chaos energy has turned into a literal force of chaos.
- Sadly, in Silver's timeline, this turned Mogul into his own spanner - because he refused to act, Princess Sally was roboticized, only being remembered as an unidentified traitor, turning her against the Freedom Fighters and helping to ravage Mobius.
- Cebolinha/Jimmy Five from Brazilian comic Monica's Gang is known for "infallible plans" against Monica. They usually work up until a certain point, when "accomplice" Cascão/Smudge screws up, usually by revealing it was a plan.
- In Tintin and the Picaros, Colonel Sponsz plots to have his old enemies (i.e. Tintin, Haddock and Calculus) be the subjects of a fake kidnapping by Tapioca's nemesis (and Tintin's old friend) Alcazar so they can all fall victim to an ambush on a back road. The spanner is a monkey in the road, which causes Alcazar's getaway truck to suddenly swerve the moment it comes into firing range.
- In the Fables spinoff The Nearly Great Escape, Jack figures out that Goldilocks is working for Revise because she wears the same style of glasses that several of his minions wear. This is a complete coincidence, but it turns out that he was right anyway.
- An early Spider-Man issue has Mysterio convincing Spider-Man that he's going insane, and then posing as a therapist who offers to help our web-headed hero. Of course, Mysterio then sets up more illusions to make Spidey think he's hallucinating again. Spidey's about to have a complete nervous breakdown when J. Jonah Jameson and Flash Thompson, who had both heard about the therapy session and wanted to support Mysterio and Spider-Man (respectively) wander into the house. When they start seeing and reacting to the same "hallucinations", Spider-Man realizes that he's being conned, and swiftly defeats Mysterio. It's later lampshaded when Jameson realizes that Mysterio was on the verge of making Spider-Man reveal his Secret Identity, and that his own arrival torpedoed the whole plan. After that, Jameson is the one who seems like he needs therapy.
- In Justice, Lex Luthor and the other bad guys come up with an extremely brilliant plan to destroy the heroes. It almost works, but they ignored a few guys like Captain Marvel, The Phantom Stranger, and The Metal Men.
- Batman, or rather Bruce Wayne, was this to the Court of Owls. For centuries they have used entertainment venues like Haley's Circus to recruit youths and brainwash them into their loyal elite Talons. They had planned to do the same to Dick Grayson (a descendant of one of their most successful Talons), but the deaths of Dick's parents and his immediate adoption by Bruce Wayne afterwards placed him out of their reach.
- Margaret from Yoko Tsuno's story The pray and the shadow. Forced by her boss to be his adoptive daughter Lady Cecilia's Body Double and be a part of his cruel plan to get said daughter killed and inherit her wealth, Margaret is shit scared of continuing in the plot, and she secretly contacts Yoko to both help save Cecilia and free herself from her evil boss...
- The Minute Men in One Hundred Bullets become this in the end. The whole series is a giant game of chess, but nobody ever thought to tell the most powerful pieces on the board. They never get a single answer to any of their questions and end up ruining every single character's master plan simply because they have nothing better to do.
- A tragic one in Batman No Mans Land. With Gotham's No Man Land status lifted, The Joker decides to squash that happy feeling by kidnapping and planning to murder every baby born during NML. In the search for the clown and the children, Sarah Essen-Gordon's radio is smashed, leading to Commissioner Gordon to tell her to head back to GCPD HQ to get a new one. What no one realized until too late was that that's where the Joker was hiding! By the time they get there, the Joker surrenders... only after shooting Sarah in the head in front of the kids.
- In the Vampirella story "The Resurrection of Papa Voudou" Paul Giraud manages to stagger into the ritual chamber, where he falls beside the altar. As a result, the spell intended to resurrect Papa Voudou splits its power between repairing the villain's mind and restoring Paul's body. Thus, Papa Voudou is raised as a sapient zombie but his body remains decayed.
- The Deadpool arc of Ultimate Spider-Man has the titular mouthy Merc being hired to kidnap the X-Men, fly them to Genoshia, and hunt them on TV. Things hit a bump when Spidey winds up brought along for the ride due to poor timing, which throws Genoshia's whole strategy out of whack. Deadpool himself sums up partway in that the hunt isn't going well because Spidey is the only thing they planned for.
Professor X: I'd like to thank you, Mister Parker. Things might have turned out very different if you hadn't been there to balance the odds in our favor.
- In the Xadhoom trilogy of Paperinik New Adventures, the Evronian plan to defeat Xadhoom fails twice because of the titular hero showing up where he had no place to be:
- initially the cruiser Zermatt is sent to capture Xadhoom for all the five seconds they need to teleport her where the Evronians are keeping hostage the Xerbians, her people, thus forcing her to surrender. They manage to do so before she grows bored and wrecks everything, but Paperinik, who has wandered around the ship, has tried some sabotage, and the teleporting device ends up sending Xadhoom back on the ship, and annoyed to boot. The Zermatt is quickly disintegrated, with Paperinik wandering through space on one of the escape pods;
- later the Evronian mobile homeworld stumble on the planet where the last free Xerbians had escaped, and use them and the other Xerbians to capture her. Thing is, Paperinik has wandered there and joins forces with the captured Xerbians, and manage to bring them what they need to assemble a device that free every single Coolflame on board (powered by Xadhoom's energy, that she provided when Paperinik showing up led one of the Xerbians to find out who she was and talk to her about their plan). And once the Coolflames and the Xerbians are in revolt, Xadhoom is free to kill the Evronian emperor, a majority of his council, and every Evronian who wasn't fast enough to run away at the first explosion.
- Fate/stay night's fanfic Chaos Theory opens up with this. It introduces the plots and manipulations of all the antagonists of FSN, and then the narrator calmly declares:
"But mostly? The assorted plans at play here would be going very, very wrong due to the actions of a no-name, no-count, utterly talentless Magus by the name of Shirou Emiya. He had no magic worth mentioning, no combat experience of note, and no plan for or knowledge of the War he was about to enter. He did, however, have one trait that had derailed a countless number of such grand, far-reaching schemes throughout history.
- In Ultimate Sleepwalker: The New Dreams, the Green Goblin kidnapped and planned to publicly murder Gwen Stacy as a way to get revenge on her father, Captain George Stacy of the NYPD. While Spider-Man intervened and tried to rescue Gwen, the Goblin had anticipated that and set things up so he'd be able to kill both Spider-Man and Gwen at the same time. Unfortunately, what he didn't take into account was Sleepwalker following Spider-Man to the top of the bridge a Cascnd distracting him long enough for Spider-Man to rescue Gwen and get her to safety. The Goblin proceeded to have a Villainous Breakdown.
- The Pony POV Series has one that's notable for the exceptionally long time required for the spanner to actually get into the villain's works. Back in the G3 Universe, which was facing The End of the World as We Know It (actually a Shoot the Dog to avert a Class Z Apocalypse) at the time, Pinkie Pie's best friend Minty just bled to death after their fight with Luna, leaving behind her "spirit" (or at least a piece of herself). Strife, Discord's sister and Spirit of Natural Selection, is fighting the survivors of the doomed world (in order to give them at least the chance to fight for their survival, something she believes is the right of all living things) and sent Heartless-like spirits of "erased" ponies after them. One of these falls into the canyon where Pinkie and Minty's fight took place, wounded in battle. Pinkie, in a split second choice, fuses the piece of Minty with the shadow, which turns out to be that of the G1 Twilight. The result? Twilight Sparkle!
- During the Dark World Arc, Discord's little sister Rancor is this. She arrives to get close to Discord and ultimately steal back Destruction's power from him so it can be used for its intended purpose (Destruction's original job as an Anthropomorphic Personification), mortally wounding him in the process. This ends up throwing a gigantic wrench in Nightmare Eclipse/Paradox's plans, allowing Discord to Out Gambit her and alert Twilight to the true nature of the Dark World, forcing Paradox to expose herself to the heroes. The name Rancor chooses after succeeding (Disruption) couldn't be more appropriate. It's this trope especially because, while its implied she knew Paradox was there, she didn't care one way or the other what happened so long as her own mission was a success.
- Part 6 of Shining Armor's Arc has Sergeant Thunderchild be this General-Admiral Makarov's attempt to kill Shining Armor. Makarov didn't even know his name, yet he shows up just in time to break through Makarov's Anti-Magic field and save Shining. This also buys time for more Shining's forces to show up in a Gunship Rescue and drive Makarov's forces off.
- In Evangelion fan-fic RE-TAKE, SEELE finds all their plans foiled by something they could never have anticipated Shinji be aided by Ghost-Asuka and "God" which allows him to destroy the Mass Production Evas during the fan-fic's take the events of "End".
- In the Mario Fan-Fic Clash of the Elements, Fawful, Alpha and Mario are this to Cackletta's plans. And Bowser too, for freeing the Star Spirits from their imprisonment.
- Nanoha's presence in Game Theory derails Precia's carefully laid plans. But this turns out to be a subversion, because the events that disrupted Precia's original strategy actually made it possible for her to come up with a better plan that works flawlessly.
- The Fairy Tail AU fic Lost Magic is an interesting example. While the deliberate wrench in Jellal's plans is Simon, the one whose mistake actually set his plot derailing was Jellal, himself. By accidentally getting himself pregnant with Erza's child.
- Jewel Of Darkness: The only reason Midnight's plan to torture Robin to insanity fails is because Ai betrays her on orders from Trigon, something she couldn't have possibly anticipated.
- Queen Of All Oni: Jade's otherwise flawless Operation: Steel Lightning only fails because of the presence of Agent Wisker, who she didn't know and couldn't plan for. He doesn't stop her, but slows her down long enough for Uncle to catch up with her and beat her.
- In Kage, Yua predicts Jade's presence in Meridian will cause Nerissa's plans to go Off the Rails, and any attempts by the elderly sorceress to force Jade to fit in her plans will only cause the schemes to unravel further. Jade is also this to the second season timeline in general, with the changes already starting to add up.
- An Alternate Keitaro Urashima repeatedly derails his grandmother's attempts to manipulate him simply by letting others know how manipulative she is. As a result, when she shows up and starts spinning her webs, she winds up proving him right.
- Mokoto also runs afoul of this when she threatens Keitaro one time too many. When she draws her katana, she's unaware that some police officers are passing behind her and witness it.
- Death Note Equestria: Mer ends up going off Twilight's script in order to ruin her in revenge for Rarity's death as a part of one of Twilight's earlier gambits. Subverted, however, as Twilight had actually anticipated this and factored it into her plans, resulting in Twilight's triumph and Mer's death.
- Ned Stark Lives reveals that Jaqen H'ghar had been hired by the Great Other to kill Jon. Arya's presence in the Night's Watch caravan completely derailed that plan, though.
Films — Animated
- Oh, the joys of Chicken Run - this is one of many visual gags, and surprisingly one that is relevant to the plot.
- The title character of Wreck-It Ralph. His desire to gain the fame and respect his rival, Fix-It Felix, Jr., had, even unwittingly, lead to Sugar Rush's King Candy being exposed as the thought-dead Turbo and the restoration of glitch character Vanellope Von Schweetz.
- Monsters, Inc.: According to Roz, Sulley and Mike were this to Waternoose's plan. She gives them credit for exposing the scandal when she reveals her own true colors.
Roz: Two and a half years of undercover work were almost wasted when you intercepted that child, Mr. Sullivan. Of course, without your help, I never would have known that this went all the way up to Waternoose.
- Olaf was this. With Kristoff having left the castle when Anna was about to die, Hans' plan may have succeeded and given him the throne. But there was no way to account for Olaf, who saves Anna.
- Elsa was also this. Her denial of Anna's marriage to Hans and her departure from Arendelle wound up saving Anna as it delayed his plans and gave Anna a lesson in trusting people so quickly while at the same time showing her The Power of Love.
Films — Live-Action
- The ending of Layer Cake has the protagonist outclassed not by dumb luck, but by being shot. Because while he was really successful in tricking clever criminals in his Batman Gambit, he ends up shot (and possibly killed, it's a little vague) by a guy whose girlfriend he stole and whom he considered of little importance.
- Carlitos Way ends in a similar fashion. After outsmarting all his enemies by the skin of his teeth Carlito ends up getting killed by some random lowlife he mistreated earlier in the film.
- Before both above films, you have New Jack City, where drug kingpin, Nino Brown, is able to fast talk his way out of serious prison time, only to get killed by an old war veteran he didn't take seriously during the film.
- Star Wars has a few examples:
- The Ewoks in Return of the Jedi are the one tiny overlooked factor that brings the Emperor's entire grand scheme crashing down.
- Luke just happens to wound Vader in the same way Vader wounded him, thus making Luke realize what he had almost become. Of course, the Emperor really wasn't helping his own cause, either.
- The Expanded Universe has the entire Imperial Fleet artificially boosted by the Emperor's force powers. The Emperor's death ended up causing the imperial officers to lose control of the situation, preventing them from shooting down the Millennium Falcon before it could destroy the Death Star 2.
- There's also Jar Jar Binks, whose clumsiness is more than a match for several tanks.
- There are about a dozen ways the Rebels lucked into the plans for the Death Star in the expanded universe. By now you'd think they had enough plans to spare.
- Anakin Skywalker's destroying the Trade Federation's droid control station in the first prequel was a massive stroke of luck. To the extent that not even he realized what was happening. He just hid in an unmanned Naboo fighter and stuff happened.
- The scheming husband in Dial M for Murder is undone because he underestimates the intelligence of Swann/Lesgate, the thug he hired to kill his wife. Swann puts the key right back after using it, rather than keeping it, as his employer expected.
- In the recent adaptation of The Pink Panther, it seems like Inspector Clouseau, a seemingly Inspector Oblivious is one of these until the very end, where he reveals that he was a Chessmaster after all. According to Peter Sellers, the original Clouseau qualified as well, but he knew he was a buffoon deep down. Strikes Again had killers from all over the world come after him. He bends over to tie his shoes at the exact right moment... Likewise in the film's Dénouement, Clouseau is unwittingly catapulted onto Dreyfus' Death Ray, destroying it and killing Dreyfus in the process.
- Sweeney Todd: The Demon Barber of Fleet Street: Sweeney Todd would have killed Judge Turpin and ended the movie right there and then in the middle had Anthony, who had recently talked to Sweeney about his plan to elope with Johanna in order to get her away from Turpin, not busted into his shop with the judge right there in the room in order to inform Sweeney that he has found Johanna and that she has agreed to the plan. Needless to say, this ends up blowing both the aforementioned plan and Sweeney's attempt to kill Turpin straight to hell.
- All throughout Pirates of the Caribbean: Curse of the Black Pearl, Jack repeatedly plots for the most favorable outcome (for himself), but stubborn fool Will Turner and arrogant jerkass Captain Barbossa assume they know best how to get things done, and nearly screw themselves out of their goals frequently. If Barbossa had wanted to cut Elizabeth's throat instead of her hand, Will would've been too late to save her on his own, and if Will had died like he should've when Barbossa ordered the Interceptor scuttled with Will trapped below, Barbossa would never have gotten Will's blood to pay Bill Turner's debt. Near the end of the film before the climactic battle, Jack has everybody where he wants them, but because Barbossa and Norrington don't trust him at all, his plans almost fall apart.
- That's what Jack WANTS you to think.
- In the 1932 sci-fi mystery film Doctor X the Mad Scientist Serial Killer manages to not only trick the other characters into believing he is innocent but also manipulates them into physically restraining themselves so he can slaughter them at his leisure. Unfortunately he forgot about the Plucky Comic Relief Intrepid Reporter, who manages to dispatch him in a terrified and bumbling fashion at the last minute.
- In The Caper film The Killing, a band of criminals pull off an elaborate robbery of a racetrack. Even though the most of the criminals kill each other off fighting amongst themselves, the Anti-Hero and his Love Interest manage to escape to the airport and prepare to board a plane out of the country with all the loot. However, all their plans are foiled when a dog runs out in front of the luggage train, causing it to crash and spill the loot all over the runway for all to see.
- In The Man Who Knew Too Little the main character foils a terrorist plot without even knowing there was one.
- By refusing to sacrifice each other, the passengers on the two boats in The Dark Knight end up being this for The Joker, in that his social experiment in proving that anyone could be corrupted ends in failure.
- In Batman Begins, Batman himself is the Spanner towards Ra's al Ghul and the Scarecrow's plan to destroy Gotham.
- And in The Dark Knight Rises, Catwoman serves as one when she saves Batman from Bane in the climax.
- In Cast a Deadly Spell, the Evil Necromancer's plan to summon Cthulhu is thwarted when it turns out his daughter was no longer a virgin due to the idiot cute cop nobody had been paying much attention to.
- The terrorists from Vantage Point might have gotten away with it, had it not been for a little girl.
- In The A-Team, Face's plan would have gone off smoothly if not for Pike having a SMAW.
Pike: Here's what I think of your best laid plans!
* Pike fires the SMAW into the ship's hull*
- Cowboy Cop John McClane's real job. When terrorists are confidently moving chess pieces behind the scenes, he knows that all he has to do is look for something sensitive and start whaling on it.
- The Adjustment Bureau tries to contain this kind of incidents. But they are not above random chance and unexpected behavior.
- Gina in Unknown (2011). Despite just being his cab driver, she saves Dr. Harris' life at the beginning of the movie and twice afterwards, killing Mooks and the Big Bad in the process, which also allows Harris to stop the plan of the Big Bad.
- In A Few Good Men, it becomes apparent that the Department of the Navy very much wants the case of United States v. Dawson & Downey to be quietly resolved by a Plea Bargain so as to prevent incident from causing too much embarrassment to the Marine Corps. This plan is undone by the dual spanners of Galloway and Dawson; Galloway, not because she is dumb, but be because she is clever enough to sense something in not right and thus goads Kaffee in doing his due diligence for once instead of rushing to a Plea Bargain, Dawson, for being too hardcore of a jarhead to willingly accept a dishonorable discharge because it would make thing easier for him, and telling Kaffee to take his plea bargain and shove it.
- In The Atomic Brain, as shown on the TV series Mystery Science Theater 3000, in spades. The main plot for the villain Miss Marsh was for her to have her brain swapped with the prettiest girl of three chosen. That gets ruined when the homeliest of the three, who had her brain swapped with the cat's, gouges her eye out. Miss Marsh's companion tries to double-cross her, killing her and letting the remaining girl take her money, but Marsh kills him. The scientist, Dr. Otto Frank, pulls one by placing Miss Marsh's brain with the cat's, revealing that he wanted to keep her locked away in the cat so he could use her money to continue his research on reviving the dead. Miss March responds by locking him in the revival chamber and setting the dial to "Frag the entire house".
- The Avengers.
- Had Thor not been there to keep the Hulk at bay the Helicarrier would have crashed and Loki's plan would have more than likely been successful.
- The arc reactor in Tony Stark's chest. It prevents Loki from mind-controlling him and turning him against his allies, which would have derailed everything just as much as the Hulk's potential rampage.
- Kirk in Star Trek Into Darkness. By threatening Harrison and offering him a chance to surrender, rather than killing him from afar as ordered, he single-handedly and accidentally derails all of Admiral Marcus' plans. And Spock, who drove him toward that decision.
- Forrest Gump calls to complain that he can't sleep because of people playing with flashlights in the next building over and so blows the lid on Watergate.
- In The Lady Vanishes an oblivious Iris manages to completely destroy a Nazi conspiracy just because she won't give up insisting that the eponymous lady exists.
- S.W.A.T.: Alex Montel kills his uncle Martin Gascoigne for sticking his hand in The Syndicate's till, then takes Gascoigne's car to the airport to catch his flight home. On the way, he's pulled over by a motorcycle policeman because he has a tail light out. The officer then discovers there's an arrest warrant linked to the license plate and detains Montel "until we can verify who you are." Lampshaded by an FBI agent after Montel's identity is discovered:
"We've been lookin' for this guy a long time. Busted tail light brings him down? That's amazing."
- This type of thing is very much Truth in Television, many real criminals are caught because of insignificant things that shouldn't have happened. One notable example is Timothy McVeigh, who was also caught when he was pulled over by a state trooper.
- In Ocean's 11, all it takes is Anthony Burgdorf's widow deciding to have his funeral in Las Vegas for Operation Pine Box to go to hell.
- This concept drives the entire plot for Dumb and Dumber. Lloyd sees Mary "forget" her briefcase while going through the airport, and, desperate to win her affection, races through the airport to snag the briefcase and return it to her: the briefcase is the drop for a ransom, containing millions, left there to be picked up by a few hired thugs. The entire plot also runs because the crooks think that Harry and Lloyd are merely Obfuscating Stupidity, never understanding that no, they are actually that dumb, but happen to thwart the criminals at every turn.
- The Black Tattoo is an incredibly epic example. Jack Farrel began as an Audience Surrogate who was only there because his best friend Charlie refused to join the secret society dedicated to protecting the world from the Scourge without him, and really had no Lehrer purpose in the main plot. Charlie's foolishness and arrogance get Jack accidentally sent to Hell, but Jack's determination and desire to help his friends eventually drive him to help Action Girl Esme stop Charlie and the Scourge, and it's his actions that ultimately wind up saving the world.
- A ditzy cultist hands the newborn Antichrist off to the wrong unsuspecting parents in the beginning of Good Omens, thus setting off a plan that derails Armageddon itself. Of course, this may have all been a bigger Gambit Roulette planned out by Powers That Be.
- In the first book of The Hunger Games, Katniss and Peeta are this because the Head Gamemaker panicked when they attempted to commit suicide and decided to make them both victors.
- Used and inverted in J. R. R. Tolkien's The Lord of the Rings. In order to destroy the One Ring and defeat Sauron once and for all, Gandalf develops an Indy Ploy / Batman Gambit to sneak the ring right under Sauron's eye into Mordor and Mount Doom, the one place it can actually be destroyed. It almost worked except the One Ring itself spans the plan by finally corrupting Frodo. Then Gollum anti-spans the One Ring's spanning by grabbing it and accidentally falling into Mount Doom. Supposedly, Gandalf knew that the Ring would ultimately corrupt Frodo, especially since it would be the most powerful within the Cracks of Doom, and that another Spanner like Gollum would have to occur for the plan to work.
- Merry, Pippin, and Sam are all Spanners to some extent as no one, not even Frodo, wanted them to come along on the quest. Even so, each one of them took actions that enabled Sauron's downfall.
- As revealed in Tolkien's other works, it's a little more a question of faith on Gandalf's part; he is literally an angel, a messenger from the divine, and he is certain that there is a god who watches over the people of Middle Earth. His cryptic comments about "the pity of Bilbo deciding the fate of many," and "my heart saying Gollum has a further role to play before the end," coupled with Frodo's growing sensitiveness to these things and his threat to Gollum that he could, "command him to leap off a cliff or throw himself into a fire" certainly hint that the Big Good Eru willed Gollum to be the Spanner.
- In Isaac Asimov's Forward the Foundation amidst the chaos surrounding high-level plots and counter-plots, Galactic Emperor Cleon I is assassinated by a totally insignificant palace minion, because he (Cleon) was insisting on promoting said peon, against the peon's fervent wishes, from "gardener" to "chief gardener".
- Gunner First Class Ferik Jurgen, assistant to Ciaphas Cain, turns out to be the one who most often saves the day, with his combination of being a "blank" who nullifies psychic powers and the fact that he carries a really, really big gun.
- Leading characters from Terry Pratchett's Discworld have acted as this on occasion:
- Witches Abroad had a Batman Gambit based on Narrative Causality fall apart before the sheer onslaught of Nanny Ogg's ordinariness.
- Rincewind never wants to get involved in events, being a coward. In Interesting Times, his great ambition is to stay as far away from the villain's Evil Plan as possible. However, he always seems to run away from danger in the direction of even more danger... until he winds up cornered and desperate, at which point he does the right thing in spite of himself.
- Some of the more inept members of the Ankh-Morpork City Watch, especially Sergeant Colon and Corporal Nobbs, fit this trope. The Watch book Thud! also has Brick the troll, who literally stumbles onto a plot to frame trolls for the death of a well-known dwarf.
- Lu Tze is a professional, very intelligent Spanner, and legendary for being so among the History Monks. The secret to his success is that no one pays any attention to the little, wrinkly, smiling old man sweeping the floors.
- The A Song of Ice and Fire book A Feast For Crows has Lysa. And Jaime. And Robb. And Allerie. And Roose. And so on and so forth. Westeros is so awash in spanners it's a wonder that it's ever experienced peace. But of course, as anyone who's finished Dance with Dragons knows, Varys is the motherfucking king of all spanners.
- As early as the first book, Bran witnessing Jaime and Cersei's incest and getting pushed out a window is a huge spanner. It was a complete coincidence and no one- not even chessmasters like Littlefinger or Varys- could have predicted it, yet it directly sparked a chain of events that would eventually lead to the War of the Five Kings, the main conflict of the series.
- Joffrey can also be a spanner at times: While for the most part he's fairly predictable, his cruelty and insanity occasionally lead him to do things that no one would expect, such as ordering Ned Stark's execution, despite his mother and Varys and Grand Maester Pycelle all telling him to let Stark join the Night's Watch instead. And let's not forget that even before he became king, he was the one who sent an assassin to murder the comatose Bran, just because he'd heard a passing comment by his father about how the boy would be better off dead.
- This is Littlefinger's entire MO: create chaos then trust his own ability to seize opportunities on the fly. This makes him incredibly dangerous and unpredictable, which in turn makes him hard to manipulate and obscures his true intentions
- Edmure Tully combines this with Nice Job Breaking It, Hero when, on his own initiative, he leads a successful attack on Lannister forces that not only derails Robb's plans to trap said Lannister force in their territory but delays them enough to receive word of Stannis' attack on King's Landing. This allows Tywin Lannister and his forces to go be Big Damn Heroes, derailing Stannis's bid for power.
- One of the lingering plot points is the state of Robb Stark's successor. Robb 's death has lead to a power vacuum in the North. Knowing that this may happen, Robb named his half-brother Jon his successor in the North, ahead of Sansa. Considering Sansa was, at the time, a political prisoner, this will screw over both the Lannister's and Littlefinger's ambitions to take control of North if this comes to light.
- The Repairer of Reputations, one of the short stories in The King in Yellow, has the evil scheme being foiled by the title character getting his throat torn out by his own Right-Hand Cat. Then again, since most people involved were insane, the plan might not have worked anyway.
- Kender, gully dwarves and gnomes in the Dragonlance series...especially (by their very nature) the kender. While all of the above races have the ability to change events in the past through time travel, due to their origins as races created by the Greygem of Gargath (pure Chaos-in-a-rock), kender have innate fearlessness, insatiable curiosity, guileless but mischievous personalities, and chronic kleptomania as racial traits. Tasselhoff Burrfoot, for example, is both the Unwitting Pawn of Raistlin's evil schemes and the only person unpredictable enough to screw them up. One of the most dreaded sounds on Krynn is the sound of a kender saying 'Oops.'
- Given the choice between being locked in a room with a hungry dragon or a bored kender, anyone with any sense picks the dragon.
- Remember, the cruelest thing one can do to a kender is lock him up. The cruelest thing one can do to anyone else is to lock them up with a kender.
- This trope is sort of lampshaded in the second Honor Harrington novel where the protagonist explains to her subordinate that the best swordsman in the world doesn't fear the second-best one, but the worst swordsman in the world, because he can't predict what the dumb son of a bitch will do.
- Apparently there is some truth in that. An inexperienced swordsman is more likely to do something that gets both combatants killed than an experienced one trying to avoid dying.
- A similar thing happens in the Age Of Unreason series, where a guy is killed by someone who cannot fence at all; he automatically assumed his attack was a mere feint, because no fencer would make such a clumsy attack. Too bad his opponent is not a fencer...
- A character in Echos of Honor is known as "Silver Spanner" Maxwell, after a Noodle Incident involving a dropped spanner produced spectacular (and expensive) results, six years previously.
- Aivars Terekhov pulls this in The Shadow of Saganami when his ship happens to encounter the same ship, using two different identities on two different planets, running weapons to terrorists on two different planets. Using evidence found on that ship, Terekhov figures out the antagonists' plan and quickly rushes to put a stop to it.
- The best part is that they only noticed the discrepancy because Aikawa, the midshipman on watch, was bored, so he ran a detailed analysis on a random freighter.
- Arnold Giancola is this on a couple of levels. His actions doctoring diplomatic correspondence led to a resumption of the war when his plan to score a political coup backfired spectacularly. Despite other characters believing he was, he actually was not part of the Ancient Conspiracy making a power grab but instead acting on his own. Later, his purely accidental death further derails investigation meant to examine his original actions.
- Mesa has been the victim of more than a couple spanners since becoming the Big Bad of the series:
- Following the Green Pines incident, they placed the blame on Manticoran agent Anton Zilwicki, as he was confirmed to be there and they Never Found the Body. Coupled with Zilwicki and Victor Cachat's transport breaking down and requiring more time to return home than they would've needed otherwise, they had every reason to think he was dead. Not only are Zilwicki and Cachat alive, they also successfully extracted Dr. Herlander Simões, a defector. So not only do they get caught in a lie, now that Zilwicki can challenge their version of events, but Simões has just enough information to alert Manticore and Haven of the Mesan Alignment.
- In Shadow of Freedom, Mesan operatives have been going to worlds on the Solarian League's borders, posing as Manticorans and offering aid to various La Résistance movements. The idea was to damage Manticoran PR by having these movements' failures appear as though Manticore offered aid then left them in the lurch. This plan is Spannered by one world seeking to contact Manticore independently, alerting them of the plan.
- John "Anjin-san" Blackthorne in Shogun is a rather magnificent one, as circumstances force him into a key role in the Gambit Pileup of choosing Japan's next shogun in the year 1600. And he's based on a real guy, to boot.
- Tom Clancy's Executive Orders: A pair of domestic terrorists spend most of the book preparing a massive cement truck bomb to kill Jack Ryan, driving it all the way across the country, dodging roadblocks put up as a result of The Virus spread by the other Big Bad of the book, only to be pulled over and arrested by a random Highway Patrolman just doing his job when they panic.
- The titular assassin of Frederick Forsyth's The Day of the Jackal seems well ahead of the international police effort to stop his attempt on Charles de Gaulle until some things come up to derail his plan. Just one of many comes up when his seduction of a baroness to gain a hiding location falls apart when said baroness eavesdrops on a call with his informant, forcing him to kill her and letting the police make him publicly wanted as a common murderer.
- And ironically, his last spanner was de Gaulle himself, who leaned forward to kiss a recipient on the cheeks instead of shaking his hand like the Jackal expected, therefore making the Jackal's shot miss and giving Lebel enough time to stop him.
- David Eddings's Tamuli trilogy reveals that the Child-Goddess Aphrael and her priestess Sephrenia were this to The Man Behind the Man without ever realizing it until his plans were exposed.
- And in fact, main protagonist Sparhawk is essentially a personification of this trope. As the "man without destiny", no one can really divine or guess what exactly he's going to do in the future...not even the gods, who are scared shitless of him.
- In James Swallow's Warhammer 40,000 Deus Sanguinius, Rafen shocks Arkio's forces by being alive. Inquisitor Stele is quite glad that he will die in single combat, because he had landed in the plans by a fluke and quickly grown to "the most serious nuisance." Of course, he wasn't dead at that point...
- Mat Cauthon in The Wheel of Time almost literally personifies this trope. He isn't stupid, but he's rarely clued into just what exactly is going on around him. Despite this he foils many schemes, especially when he's actively trying not to.
- And similar to the line mentioned in Honor Harrington above, when the White Tower's weapons master tells Galad, Gawyn, and Mat a story about history's greatest swordsman, who was only defeated once in his entire life - by a random farmer with a stick.
- The War of the Worlds is essentially one long Curb-Stomp Battle with the invading Martians effortlessly rolling over all of humanity's attempts to stop them. Then a month later they all die of common Earth diseases, germs and therefore antibodies being non-existent on Mars.
- In the last The Chronicles of Narnia novel, The Last Battle, the villains come pretty close to winning. What ultimately derails their schemes? Oh, just that the demon lord Tash really exists.
- In Rainbow Six, Eddie Price's pipe-smoking after success missions is the first in a series of little things that clue The Dragon in to the true nature of Rainbow despite efforts to hide it. Carlos the Jackal's fellow criminals, in carrying out an attack to try and get him freed, gets the team some good publicity that gets them to view the Sydney Olympics for free and puts them in the right place to foil a vital part of the villain's plan. One of the villains' captives manages to get off an email, the investigation into which eventually helps lead the way to them. One of the named minions tells The Dragon, hitherto ignorant of the truth, about the extent of the plan, prompting a vital Even Evil Has Standards moment that causes him to go to the good guys with the information, allowing the case to be cracked.
- In Stephen King's The Stand, Randall Flagg (the demonic Big Bad) recruits Trashcan Man and sends him out into post-apocalypse America to look for stuff with which to destroy the good guys. He brings back a literal Deus Ex Nukina just in time to destroy the city of Las Vegas while Flagg is distracted trying to tear the remaining heroes limb from limb.
- In the Dale Brown novel Executive Intent, Wayne Macomber would have avoided capture by GRU agents had he not stumbled over a random civilian in the wrong place at the wrong time, who proceeded to inform the police and make the already suspicious GRU agents take action.
- John Lennon's short story "A Spaniard in the Works" has very little to do with this trope. Or, for that matter, anything else.
- In Bystander the villains run into a very severe example of this, when they have a great plan to capture Lucretica, and are foiled by two details. One, they have a severely incorrect estimation of her power level, and two: Her feet don't touch the ground.
- In Harry Potter and the Half-Blood Prince, Draco Malfoy's act of disarming Dumbledore completely derails the gambits that both Dumbledore and Voldemort had in place in regards to the Elder Wand. Though with a bit of luck it ends up working out great for Harry himself.
- Fireheart in Warrior Cats. He completely ruins Tigerclaw's plans by running into the cave where Tigerclaw was during a battle and beating Tigerclaw up.
- In The Dresden Files novel Changes, they are able to narrow down the location of where the sacrifice will occur because even though the records for the first shipment were destroyed, the red court still had to transfer another shipment due to the fact that the previous shipment was incomplete due to minion carelessness. As such they needed to keep one copy of the records intact until after the final checkup and they kept the records in the van they needed to use to transport the goods. As such Harry is able to narrow it down and eventually find Chichen Itza, enabling him to blow the Red Court's plan sky high.
- In Queste, the fourth book of Septimus Heap, Jenna and Beetle are this to Tertius Fume's plan to kill Septimus with the Queste.
- In The Dance of Time, the final book of Eric Flint's Belisarius Series, there is a side plot of a Malwa assassination team tasked to kill Byzantine Emperor Photius and Empress Tahmina but keeps getting foiled by unexpected changes of plans of their targets. The team follows them for thousands of miles while the plot of the rest of the novel occurs around them. At the end they run across the fleeing Malwa emperor and the Big Bad (currently inhabiting the body of an eight-year old girl). They kill him and his guards and wound her which makes it possible for the good guys to finally achieve complete victory. They get rewarded by being sent into exile with the series' Manipulative Bastard.
- In The Demon Headmaster books, Dinah manages to be both this and an Unwitting Pawn at various points. The Headmaster can easily hypnotize her, and she's very close to being his greatest asset, but she's just intelligent enough to shake it off and bugger it all up at the last minute. For the record:
- Book One is the one where they meet. He doesn't know her capabilities.
- Book Two has him not knowing her new name.
- Book Three has him not even realising she could figure it out.
- Book Four has him specifically targeting her for her DNA.
- Book Five has his clone, who doesn't even know she exists. Dinah stumbles on this one purely by accident.
- The final book has him attempting to demoralize her. He almost wins, and would have had Dinah not had a last-second burst in hearing capability.
- In one of Francoise Rivier and Michel Laponte's Jonathan Cap books, recurrent character and local Plucky Girl Juliette becomes this. She has her appendix removed in a Parisian private clinic and notices that both her doctor and the nurse in charge of her are acting strange, notifying Jonathan's Kid Sidekicks Alex and Nico about it so they can call Jonathan and investigate. It turns out the doctor is the Big Bad of the book, with a complex plan involving an Arabian prince and his Body Double (the Big Bad's "disciple"), and the nurse is his forced accomplice because he threatened to kill her if she didn't collaborate. The plan would've gone smoothly, had the Big Bad not been pretty much forced by the circumstances to be the doctor in charge of Juliette's emergency surgery...
- In the historical novel Wings of Dawn: Thomas, to the Druids. Umar and Hadad, to Sir William. The Mamelukes and the bandit troops, to everybody.
- Mark Twain's short story "Luck" speaks of Lieutenant General Lord Arthur Scoresby, V.C., K.C.B., etc., a complete idiot who got on the fast track to war hero-ism because he got his left and right mixed up in battle and accidentally led his regiment right into where the other side was preparing a surprise attack, and drove the ambushers into full retreat because there was no possible way they would be discovered in time, and so didn't prepare.
- Miss Emily Dorothea Seeton, created by Heron Carvic. She's difficult to describe. As far as she's concerned, she's a retired teacher the police use as a sketch artist, not an amateur investigator. So when the bad guys come after her, she usually has no idea why they're doing so. Her reactions usually end up with the villains in custody, the case closed, and quite possibly police trying to write reports that make sense.
- In The Maze Runner Trilogy, Thomas and Minho finally get in on some Spanner action at the beginning of The Death Cure . Everything previous to that was planned by WICKED and there was no point at which they were not under WICKED's control.
- in Academ's Fury, Sarl and the Vord would have won if it wasn't for one person: Canim ambassador Varg. He managed to figure out their plan, and because he doesn't like the duplicity involved, goes out of his way to stop it. They did plan for him, but they figure that because he is hated, nothing he says will be believed. And they would have been right, had Varg not ended up skipping diplomacy and outright dragging Tavi to the Vord nest, alerting Tavi to the threat and allowing him to prepare.
- Tavi's aunt Isana was also an unknown factor. She knew about the Vord from Calderon, and it was because she cut a deal with the Aquataines (whom she had hated before) to get support for the legionnaires fighting the Vord in Calderon, and got Invidia Aquataine to counterattack the Vord, breaking their attack.
In Elsabeth Soesten No Good Deed...]]
Elsabeth and Hieronymus accidentally foil Cuncz's plans to steal incriminating information about himself from Father Garnerius when Garnerius hires them to recover the reliquary (where the Abbot stashed the documents) stolen by Cuncz's agents. Cuncz just shrugs off the setback and hires them to finish the mission instead.
- In the Past Doctor Adventures novel "Corpse Marker", a complicated Batman Gambit is in progress when the Doctor and Leela arrive. Over the course of the book, the plan slowly falls apart thanks to their presence (and another complicating factor the planner didn't know about).
Live Action TV
- In the Doctor Who story City of Death, Duggan, the detective who seems to have gotten into his line of work just because he likes hitting things, derails the villain's multi-millennial scheme with one thoughtless, well-timed punch.
- In the episode The Pirate Planet, after all the planning to destroy the Mentiads by both a cyborg pirate captain and a tyrannical Queen Xanxia in disguise, the Mentiads and the Doctor manage to do this trope... literally.
- In the story "The Caves of Androzani", unusually, the Doctor's role in the story is limited to frantically attempting to get him and Peri out alive. His mere presence, however, inadvertently causes the entire messed-up Androzani society to implode. The Doctor brings down a corrupt government accidentally.
- Generally speaking, the TARDIS spends her days throwing herself, the Doctor and his Companions at various intricate plots specifically so they can act as nifty spanners, just by dint of shuttling between crisis points, whenever they may be. *VWOOP-VWOOP-VWOOP* is the sound of somebody's ten-step plan starting to belch smoke.
- Get Smart, of course; Maxwell Smart is more likely to defeat KAOS by accident than on purpose.
- A British Sketch Comedy program parodied this. A man is buying a camera, and is shown one that is "totally idiot proof". He then smashes it on the table. "What did you do that for?" "Well, I'm an idiot." The shopkeeper then shows him a camera made out of concrete.
- In an episode of Wallander, the title character avoids a fatal bullet by tripping over a conveniently-placed rug.
- In TNA, Taylor Wilde and Lauren Brooke derailed Dr. Stevie's attempts to turn Abyss into his puppet. Despite using drugs, physical abuse, and mind games to keep him in line, Dr. Stevie didn't count on Abyss falling in love with Lauren. Then, when he ordered Abyss to attack Taylor, he didn't count on her being Lauren's best friend...
- Married... with Children: Kelly Bundy tended to mess up whatever plan she became involved in, given her role as The Ditz and Brainless Beauty. It's even lampshaded by Peggy at one point as the Bundys and the D'Arcys are being arrested by the police, when she notes that it probably wasn't a good idea to let Kelly in on the plan.
- Angel has this when a sorcerer's plan to sacrifice his virgin daughter for power is thwarted when it turns out she hasn't been a virgin since she was in her teens. She even dated one of his mage bodyguards, who probably knew that she had to be a virgin for the sacrifice to work, and shuffles awkwardly offscreen after she points him out.
- The Season 5 finale of Weeds features an unusual instance of a smart character acting as fate's tool: Shane Botwin's murder of Pilar, a brilliant criminal who acted as puppeteer for Estaban, the Mexican stock exchange, and Mexican government as a whole. Essentially, Shane and his croquet mallet accomplished in a mere second what Nancy and Guillermo had failed to do in half a season, and those two burnt down an entire town without getting caught...
- Firefly has a rare example of this happening to the hero. In "Objects In Space", River's Batman Gambit to lead Early onto the top of the ship where Mal can ambush him is almost dashed by Simon trying to stop Early, unaware that River is actually prepared to ambush Early and not simply surrendering. Fortunately, Simon's woeful lack of skill in combat means Early is able to beat him back in time to waltz into the trap.
- SG-1 was once called to help Thor to serve this very purposenote .
Jack O'Neill: So what you're basically saying is you need someone dumber than you?
General Hammond: I'm sorry, Thor, but we need SG-1 here.
Sam Carter: I could go, sir.
Jack O'Neill: I dunno, Carter, you may not be dumb enough.
- In the third series of Primeval, Helen has a plan to kill the first hominids and thus erase humanity from existence. She very nearly succeeds, if not for one desperately hungry raptor.
- The main characters in The Good Guys are generally competent cops (yes, even Dan Stark) who solve major crimes largely by stumbling into them while investigating something much smaller.
- Shotaro Hidari, despite being the main character of Kamen Rider Double, gets this from every single one of the show's Chessmasters. Neither Ryubee Sonozaki nor his wife Fumine, AKA Shroud, ever considered that the overly emotional and all-too-human detective could possibly be a factor in their plans, especially since Ryubee's Terror Dopant form emits such raw Primal Fear that Shotaro can barely think in his presence, and Shroud was planning on partnering up Ryu Terui (Accel) with Philip since they're both immune to that effect. Neither did the True Final Boss Jun Kazu, the Utopia Dopant, thanks to his Reality Warper powers. Shotaro manages to show them all up, overcoming his limitations with a combination of Hot Bloodedness and loyalty to his True Companions that lets him make the impossible possible, even defeating Utopia without transforming into Double. Arguably lampshaded by Shotaro being tied heavily to the concept of the Joker — he's both the Wild Card (the element nobody saw coming) and the Trump Card (the key to victory).
- In Heroes Vs. Villains, Tyson served as a Spanner In The Works for Rob's gambit by serving as an Unwitting Pawn in Russell's gambit. The Villains tribe was divided between Rob's and Russell's supporters, with Rob leading 6-3. However, Russell had an immunity idol, which meant that when the tribe voted someone out, he (or whoever he gave the idol to) could stand up and play the idol to prevent any votes cast against them from counting. Rob wasn't sure whether the idol would be played by Russell or by Russell's closest ally, Pavarti, but Rob had a plan to guarantee they could get rid of either Russell or Pavarti. He would have three people vote for Russell and three for Pavarti; then, regardless of who played the idol, the other one would have three votes. Even if all three people on Russell's side voted for one person, it would have meant a 3-3 tie between votes to get rid of Russell or Parvati and votes to get rid of whichever Rob supporter Russell targeted, leading to a tie-breaker that Rob's side could easily win. However, the plan fell through because Tyson actually let Russell (his alliance's enemy) tell him who he should vote for. Rob had assigned Tyson to be one of the three people to vote for Russell. However, Russell told Tyson that he would sacrifice Pavarti and use the idol to protect himself, leading Tyson to think that he should vote for Pavarti because votes against Russell wouldn't count after Russell played the idol. Russell had other plans, and gave the idol to Pavarti. After the votes were cast, Pavarti played the idol, meaning that the final vote count was four votes (including Tyson's) against Pavarti that didn't count, two votes against Russell, and three votes cast by Russell and his allies against... Tyson. It was three to two, and Tyson was sent home. Afterward, Tyson admitted to the camera, "I am a victim of my own stupidity." His action was one of five official nominees for the dumbest action in Survivor history.
- Sash fell victim to three Spanners during Nicaragua. He was in a very good position in the game, having just ousted Chessmasters Marty and Brenda in quick succession, but then his closest allies Kelly and NaOnka decided to quit at the same time, leaving him without an ideal final three (Kelly did very little in both strategy and physical play, and NaOnka was universally disliked by the other tribemates). He managed to quickly get himself into a secret alliance with Chase, Holly, and Jane, but then Fabio, who was both the alliance's obvious target and had been faking the part of the Dumb Blonde up until that point, planted the idea in Chase's head that Jane needed to be taken out before anyone else. Sash proceeded to make the plan his own, which in turn led to Jane revealing the alliance at the next Tribal. From there, Sash could only helplessly watch as Fabio went on a string of Immunity Challenge runs, keeping him safe to the very end, which forced Sash to turn on his alliance and vote out Holly. The end result? A Final three of Sash, Chase, and Fabio, with Chase getting four votes, Fabio winning with five, and Sash with... none at all.
- An episode of Fringe features a villain whose intelligence was boosted so he can perfectly predict anything that will happen and set up ridiculously complicated scenarios to kill people and escape from the agents chasing him. He's foiled by Olivia not actually being from his universe, just brainwashed to think she is. So she doesn't recognize a sign indicating a low oxygen area, and doesn't pause to grab an oxygen mask, allowing her time to dodge the stack of pipes he thought would kill her.
- This trope has made the lives of the investigators on CSI much, much easier over the years. Whether it's people discovering a dead body before it can be completely dissolved or buried, witnesses who unwittingly provide evidence that ties a murderer to a crime scene, or a Heroic Bystander who catches a Peeping Tom that also turns out to be a serial rapist, various members of the public have helped the CSIs bring a lot of criminals to justice in many different ways.
- Tragically, Lancelot became this for Arthur and Guinevere on Merlin despite repeated promises to himself and Merlin that he would never come between them. However, Morgana resurrects him after his Heroic Sacrifice, robs him of his free will, and forces him to seduce Guinevere (who was enchanted to respond to his advances).
- In the first volume of Heroes, there was a large and complicated plot that involved blowing up New York in order to usher one of the characters into the White House. The only thing stopping it from being a Gambit Roulette was the fact that the people responsible were basing their convoluted plot on the works of an artist who could paint the future. And it was working, hell, it almost did work. Unfortunately for them, a certain Future Badass with the power to control the Space-Time continuum didn't like the result, and traveled back five years to give a message to one of the present day characters. This guy had no idea that there was any sort of plan, he just thought it all happened naturally, but the message he delivered set off a chain of events that ended up ruining the plan at the last minute.
- Leverage: In "The Gold Job" Hardison demands, and is given, the opportunity to run his own con by Nate. Hardison plans an elaborate Batman Gambit based on video game theory and it's working very well, until the people he's manipulating decide that it's not worth the effort to keep jumping through his hoops. In an ending scene Hardison receives a letter Nate wrote earlier in the day which outlines the three things the plan needed to succeed (which Hardison's plan made possible). Nate then explains how he plans his cons to anticipate the possibility of spanners; he starts with the crude, ugly basic plan, and then plans the elaborate, beautiful, intricate plan from there.
- Supernatural: Naomi calls Castiel this by name, and says that he has never followed orders.
- The Winchester brothers might also qualify, as it is their unwillingness to do as they're told that derails the angels' apocalypse plans.
- Salem: John Alden's mere presence in Salem is screwing up the witches' preparations for their Grand Rite. Increase Mather later becomes this as he basically appoints himself the inquisitor of Salem.
- In Brooklyn Nine-Nine, Captain Holt and Sergeant Jeffords begin to secretly "CompStat" the precinct office in order to meet a paperwork deadline, by secretly manipulating the detectives in order to increase efficiency. Unfortunately, both of them forgot that Detective Peralta was out of the precinct while they were doing this; when he gets back to find Detective Scully moved to his desk, Peralta shoos Scully away to the break-room, which leads to a chain of events which sees Scully accidentally start a fire and bring the whole thing crashing down around them.
- In just about any D&D module, the adventurers are the Spanner. And any good GM has to be able to handle a Spanner, as the PCs can be expected to do the one thing the GM hasn't anticipated.
- A mediocre GM can do this to players. When the players have a good plan which bypasses the intended challenge handily or solves a challenge with minimal fuss, a good GM may let the players have their moment in the sun and save those encounter notes to recycle them with new window dressing. A mediocre GM will have the players' plans fail for increasingly implausible reasons. A poor one will have a deer in headlights look as soon as the players are Off the Rails.
- Example: Give the PCs the Eye of Vecna, you get some fun people fighting over it. However, one of the PCs sacrificing the Eye of Vecna to THE GOD OF JUSTICE? Not so expected.
- In Unknown Armies, you can become an Avatar of an archetype by mimicking that archetype's classical behavior. One of those is The Fool, who can pull this off easily and walk away unscathed.
- In Chrononauts, new players are the spanner. Plans in the game range from Gambit Roulette to "I win next turn as long as no one makes a minor change in 1914". New players will often meddle with history (even starting World War III), steal random historical artifacts, or kill the makers of said artifacts, to "see what happens".
- In Exalted, beings that exist outside of fate are the ultimate Spanners from the perspective of the Sidereals. Since they cannot be detected, manipulated, or predicted by fate and fate-based powers, one of these beings can derail centuries of careful planning before the Sidereals realize that anything's amiss.
- In Vampire: The Requiem, the Circle of the Crone has the position of The Fool, whose sole purpose is acting as this. When the Circle needs something stopped they send in The Fool and watch stuff blow up. Basically it's like "so, you're a rather spirited walking corpse, eh? Say, could you go check out what that Invictus bastard is doing downtown? Just do whatever feels natural, I'm sure it'll be a blast." Fools who survive long enough to gain some measure of respectability might make it to the rank of Trickster, for whom the purpose is basically the same except the Trickster actually has some idea of what he is doing.
- A common meme in Warhammer and Warhammer 40,000 is to label the defeat of Tzeentchian and Eldar forces as "Not As Planned"; as the smug bastards claim any victory is "Just As Planned".
- In ''Tabletop Game/Champions 5th edition universe, The centuries long, multi-dimensional, wheels within wheels master plan of DEMON's secret master involves in it's final stages a literal Spanner in the Works. The precise timing that underlies the multiverse needs to be off just slightly for the rest of his plan to work and as such he has positioned a minion in the the metaphysical boiler room of creation with a $10 hardware store spanner. Now he just needs the stars to align....
- Cyrano de Bergerac: Played hilariously straight: This play (a farce) has a lot of Gambit Pileup orchestrated by Cyrano, Roxane and De Guiche, but no one of them is capable of being an Unwitting Pawn for long.
- Cyrano: Lampshaded by himself at Act II Scene VI: Unaware of it, he destroys De Guiche plan to set an arranged marriage with Roxane and De Valvert when he manipulates De Valvert to a duel.
Cyrano: (Bowing to Roxane):
Then I fought, happy chance! sweet lady, not
For my ill favor—but your favors fair!
- In Grandia II, this role goes to Millenia. The Big Bad's plan requires that all eight pieces of Valmar be absorbed by Millenia so that Valmar's resurrection can be brought about and the Big Bad can merge with him. What the villain didn't count on was Millenia refusing to absorb the Horns after they merged with Ryudo, and then sealing them inside Ryudo rather than risk killing him. As a result, not only was Valmar's resurrection incomplete, but Ryudo eventually used the Horns as a weapon to kill the villain.
- In The World Ends with You, Neku points out to a Manipulative Bastard that it is utterly impossible to predict what Beat is going to do. Heck, if you collect the Secret Report after the end of the game, even the Angel, Mr. Hanekoma, thought Neku was screwed before Beat's Heel-Face Turn, which was conveniently possible because of his Face-Heel Turn in the first place.
- Persona 3. After his Reveal as The Chessmaster, Shuji Ikutsuki plans to sacrifice most of the party by forcing Robot Girl Aigis to murder them in order to bring about The End of the World as We Know It. He's just about to succeed... but at that point, the player is reminded that he forgot to crucify the dog, too.
- White Knight Chronicles: You are this for Bigger Bad Emperor Madoras. Or, rather, your custom character is. (The game features an incredibly robust character creation system, and it's an unwritten rule amongst the fandom that the avatar be based off of the player.) After sitting back silently during the story mode while (most likely, should you choose to play the game's plethora of side quests that require your avatar) being the most devastating character in combat, you are the only one able to take on Madoras in the game's bonus dungeon.
- World of Warcraft: Every raid dreads the Leeroy Jenkins, who can ruin an otherwise carefully arranged plan of attack by charging in headfirst.
- In Wrath of the Lich King, after Drakuru plays you for an Unwitting Pawn, you get to do this to his plans repeatedly.
- Xenosaga: The entire plan of the Big Bad, that has taken centuries and all three games to complete, is undone because Allen can take a beating and look really pathetic while it happens. It's more awesome than it sounds.
- A much more minor, but hilarious, example comes from Chrono Trigger. Ozzie, inept sidekick to the great Magus, was originally defeated by being dropped down a Trap Door. In his second coming, he's smart enough to make the switches instead drop the heroes down the trap door. When they come back, Ozzie's ready for anything... except for a not-so-random cat (if you get the regular ending, Chrono's cat(s) jump into the time portal), which wanders in, flips the wrong switch, and down he goes...
- In Soul Nomad & the World Eaters, Lujei Piche apparently is stated to have ruined the effort involved in banishing Sulfur of Phantom Brave, sending him back to Ivoire as a Bonus Boss.
- Revya and Gig, for all the multiple times they are Unwitting Pawns during the storyline, also become epic spanners: The demon path is basically you laying waste to the entire Gambit Pileup: Virtious, Thuris, Dio, Rashka and all the other manipulators' year-long plans are ruined by one free-roaming Omnicidal Maniac doing it For the Evulz.
- Final Fantasy IV offers a minor example in the Dark Elf. A monster who messed up Golbez's plans to steal the Earth Crystal from Troia by snatching it first and running off to a cave where he rendered metal weapons unusable. Golbez works around this by sending protagonist Cecil to fetch the crystal in exchange for Rosa.
- Believe it or not, Vaan from Final Fantasy XII fits this role very well. While he appears to be simply a throwaway character, he is the only one besides Ashe to see a loved one's image projected by the Occuria, in this case, his brother Reks. This implies that the Occuria felt that he would be a suitable and effective 'Plan B' to become the weapon which would destroy the Archadian Empire in revenge, should Ashe falter, probably due to his being both Dalmascan, and for, at the start of the game, harbouring resentment towards Archadia for the death of his brother. Instead, Vaan actually overcomes the illusions much more quickly than Ashe, ultimately providing a more virtuous role model for Ashe, as seen when he refuses to take revenge on Gabranth for killing his brother. He may just have been the push she needed to reject revenge at the story's climax.
- It's not so easy to see because he's a minor villain, but the Dark Elf King Astos has been at his plot for years, then the Warriors of Light come out of nowhere, on a completely unrelated quest, and straight up murder him. And while it might seem like Astos spanned his own plot, his theory was that the artifacts he tricked the Warriors of Light into getting him would make him all-powerful, so revealing himself isn't stupid so much as Genre Blindness.
- Dissidia 012 also retcons it that just one Warrior of Light, who is a Manikin. This guy is such a spanner that he manages to bring down plots in two worlds without even knowing his own name, let alone his ridiculously complicated origin story.
- Ash DragonBlade's story in Dragon Fable from Artix Entertainment consists of Ash foiling the plots of would be Big Bads through his own sheer stupidity.
- In La Pucelle Tactics the plans of both Noir and the spirit infecting Croix are foiled not by the Maiden of Light, but by Priere, a newbie priestess who is perhaps the least likely person you'd expect being a nun, though she has a mean right hook and an even meaner set of legs.
- In Final Fantasy Crystal Chronicles: Echoes of Time, Larkeicus does this to ''his own'' plan. He builds a tower to reach the point in the sky where the hero's going to cause the crystals 2000 years ago to vanish, and prepares for every possible outcome, including his own defeat. Too bad he forgot to consider how the hero would get that high up in the first place.
- In Evil Genius, this can easily happen to the player if (s)he gets careless. Even the lowest of the agents of justice can become this if you neglect to pay attention.
- Ditto Dwarf Fortress; the tiniest breach in your defenses (like a monarch butterfly flying into the main door and jamming it open) can lead to goblins cutting a swath through your dining hall, or a fortress-wide tantrum-spiral.
- General Shepherd didn't expect one thing in Modern Warfare 2. SAS Captain John Price. Price firing the nuke at Washington caused Shepherd to resort to some Xanatos Speed Chess and move up his timetable for TF 141's disposal, but Price's willingness to co-operate with Makarov pushed him on to the defensive and gave him a knife through the eye.
- In The Force Unleashed, the cunning plan created by Vader and Palpatine fell apart due to one bit of (bad) luck and one unforeseen relationship. The accidental wiping of PROXY's primary programming resulted in a Heroic Sacrifice when Vader tried to kill Starkiller, and the emotional connection between Juno and Starkiller meant she came back and rescued him after Vader's failed attempt to kill him. Starkiller himself then became the spanner when he went after Vader and Palpatine, saving the rebel leaders. The end result is that Palpatine and Vader ended up creating the Rebellion that eventually defeated the Empire. Oops.
- The Alien protagonist in Aliens vs. Predator 2.
- In Mega Man ZX, the cornerstone of Master Albert's plan to become a god involved gathering the world's Model Ws and combine them into Ouroboros. However, aside from shitting out Mavericks like an Ominous Ring Of Land, it has no way to prevent an airship from crashing into it and inserting a war party intent on shutting him down. If he had a few more Model Ws, he could have sprung for mounted anti-air... too bad the Guardians (and Mega Man Model ZX) got to them first (and subsequently destroyed them). The thing to note is that this is a Spanner entry because Albert's plan would have been more complete had they not been destroyed; everything else went just as planned.
- Actually the better example is how a pair of excavators accidentally awaken Grey, Master Albert's back-up body. After witnessing what Model W can do, Grey ends up saying no to Master Albert's plan and becomes instrumental in his downfall. Ashe also counts since in her storyline, she encounters Model A by accident and singlehandedly ruins Albert's plan as well.
- Albert even notes that her appearing was entirely unpredicted, and the amount of trouble she caused for him surprised most people directly involved.
- Sora and Co. from Kingdom Hearts have an innate ability to utterly ruin the numerous complicated plans that people form around them without having the slightest clue of what's really going on.
- Team Fortress 2 - While the Spy's entire job is to be the Spanner in the enemy team's works, random chance tends to play this role in otherwise evenly matched teams, as nobody can account for that stray lucky critical hit.
- The protagonists of Silent Hill tend to be played for Unwitting Pawns —but they will also send the bad guys plans spiraling into complete disaster because their goals don't involve unleashing an Eldritch Abomination on the world.
- Fear 2: Project Origin has this happen to the player instead of the villain. Terry Halford comes up with a telesthetic amplifier that could give the player character, Sergeant Beckett, a decent chance at exploding Alma's head, and then Genevieve Aristide waltzes in, shoots any dissenting voices, and changes the amplifier's settings in an attempt to trap Alma. Note that Halford, who has a far better grasp of the math and science of the amplifier, has already stated very emphatically that Aristide's plan simply will not work and Aristide is essentially a desperate idiot trying to make reality conform to her wishes. Her pitiful attempts only make Alma stronger, at your expense.
- In Vampire: The Masquerade – Bloodlines, the player character skews the very, very delicate power balance of Los Angeles simply by being Embraced. That's about the only time things are not going according to someone's plan, though, and is directly followed by Xanatos Speed Chess on the part of Jack, LaCroix and Caine, rather than a Villainous Breakdown on anyone's part. In the endgame, it is impossible for you to be one, because whatever you do, LaCroix is toast for one reason or another.
- King's Quest:
- King's Quest VI: Heir Today, Gone Tomorrow: Grand Vizier Abdul Alhazred has been running an Evil Plan very successfully on the Land of the Green Isles. Gain the trust of the king and queen and their approval to marry the princess then arrange the kidnapping of the princess and kill the king and queen, making sure he's in charge. Spread rumors and encourage in-fighting among the islands to bring the kingdom to the brink of civil war after stealing their sacred treasures yourself and crippling the only non-magical means of transport so they can't visit each other and check. As the final piece, arrange a grand sham wedding to the princess and kill her after the wedding night. It's running like clockwork, and then the Prince of Daventry shows up with a mad crush on the princess...
- King's Quest VII: The Princeless Bride: Malicia has kidnapped the Fairy Prince Edgar and the Troll King of the Volcanix Underground, then transformed and brainwashed the former to impersonate the latter and cause a volcanic explosion that will destroy the Fairy Kingdom of Etheria. But she didn't realize that her new accomplice harbored feelings for a certain Princess of Daventry and that his now morally deficient state would cause him to kidnap her, causing her mother to chase after her... and things kind of fell apart after that.
- Speaking of Sierra, the Hero in the Quest for Glory series tends to be this at times as well, either by intent or accident. Basically all of Quest for Glory IV was a result of the teleport spell used to snatch him at the end of Quest for Glory III dumping him in the wrong place in Mordavia.
- Sierra loved this one, because much of Space Quest ran on this as well. Roger Wilco had just the good (or bad) luck to send the best laid plans careening into a cliff.
- The first game? The Sarians had boarded the Arcada, stolen the Star Generator, and slaughtered all of the crew...except Roger, who had been taking an unscheduled nap in the broom closet.
- The second game? Vohaul had his cloned army (granted, they were an army of insurance salesmen) ready for launch, but having his Mooks sent to kill Roger in an attempt to prevent him from stopping it (after all, Vohaul bankrolled the Sariens), led to Roger showing up and wrecking the plan anyway.
- Third game? Roger was just good enough at Astro-Chicken and just bored enough to find and investigate the secret message from Pug's captive programmers.
- Fourth game? Once again, Vohaul tries to pre-emtively kill Roger from screwing up the plan. But the timely arrival of Xenon's time-traveling La Résistance sends that into a tailspin.
- Fifth game? Captain Quirk was above suspicion, captain of the Confederation flagship. No one was going to investigate some toxic waste dumps on a few backwater planets. They all but laughed the ambassador representing those backwaters out of the room when she tried to call attention to the problem. But then a mouse chews up some wires in the academy computer, Roger gets accidentally promoted to Captain, and guess who finds out about Quirk's lucrative side business in transporting tetragenic sludge?
- Sixth game: Stellar the the spanner. Sharpei wanted to commit Grand Theft Me on Roger, figuring he wouldn't be missed. But Stellar steps in at the last minute, makes a Heroic Sacrifice, and Roger decides he's going to rescue his pal. Sharpei and her plan did not survive.
- Fire Emblem
- Fire Emblem 7 has Kishuna and Hector. The first one ruins a Smug Snake magic user's trap for the heroes via his Anti-Magic powers, the second is such a strong support for Eliwood that Nergal has to admit that his mere presence throws his gambits around Eliwood off.
- In Fire Emblem Jugdral, Manfroy's Stalker with a Test Tube plan to have the perfect Soul Jar for Evil God Lopto did work… but was thrown off by how the mother of said Soul Jar gave birth to twins... and the sister of the Soul Jar actually had the Sacred Blood needed to handle the perfect weapon to vanquish Lopto away. And then the girl was spirited away by her dying mother and later was "adopted" by La Résistance…
- In Fire Emblem Awakening, one of these appeared in the backstory. The Grimleal aka the local Religion of Evil has carried a Super Breeding Program for at least four generations, trying to have a baby conceived with enough Grima blood in him/her to make him/her the perfect host for Grima, the Evil God of the story. They didn't count, however, on the mother of the last baby and most perfected Grima prospect vessel actually changing her mind and running away with her son/daughter rather than allowing his/her father, Evil Sorceror Validar, use the baby for such deals. Thanks to this, the prospect vessel grew away from the Religion of Evil... and became the Avatar aka the Protagonist of the game.
- The Big Bad of Last Scenario had such a good plan going until Phantom woke Ethan up early. Then Ethan just happened to run into an Unwitting Pawn and warned him not to trust an agent of said Big Bad. Things kinda fell apart from there.
- This is basically all the Boss does in Saints Row 2. The Brotherhood originally planned on bringing in a shipment of weapons to take over the city with. Boom, the Boss steals it all. Then they try to manipulate their friends out of jail. The Boss just kills all of them when they get out. The Sons of Samedi see their plans to sell drugs ruined by the Boss when he kills all their dealers, and when a lieutenant tries to trick the Boss into walking into traps, the Boss kills them too. Vogel, meanwhile, planned to manipulate everybody into killing each other so he could take his place at the top, which worked fantastically when he was getting the Boss to kill people instead of getting people to kill the Boss.
- Raphael Sorel, the French fencer from Soulcalibur II, unintentionally saved the world and Siegfried (here in his guise as the Big Bad, Nightmare). Raphael appears as Nightmare's opponent in his Destined Battle. When Nightmare defeats Raphael and is about to finish him off, Siegfried is somehow roused out of his suppression by Soul Edge/Inferno and begins a Battle in the Center of the Mind, rendering his body immobile. Seizing the opportunity at hand, the injured Raphael takes his rapier and delivers a mighty thrust to Soul Edge's eye, weakening the soul of the sword and allowing Siegfried to fully regain control of his body. At that point, the holy sword Soul Calibur appears to aid Siegfried, who then plunges it through the evil sword again. This causes both swords to fall silent (having been locked into a state that rendered both dormant), setting up the plot of III and Siegfried's character progression to that of The Atoner. Raphael's reward? He gets infected by Soul Edge's malevolent influence (he unwillingly passes this on to his adoptive daughter Amy as well, when she tends to his wounds) and becomes some sort of vampire.
- In Advance Wars 2, despite Andy having a spanner himself, It's Hawke's turn against Sturm that really destroys his plans.
- In the chapter 1 finale of Dragon Fable, the Big Bad is undone by two spanners. The Bacon Elemental Orb (which no one but Cysero knew even existed until that moment) combined with Cysero's time machine gives the hero and his dragon a fighting chance in the Final Battle. Just when it seems like even that wouldn't be enough to save the day, the villain's host body Fluffy reveals his weak point to the hero and his dragon.
- GrimGrimoire has the The Archmage preparing to break free from his Soul Jar and take the philosopher's stone and menace the world, and powerful devil he entered a pact with named Grimlet is about ready to break from being sealed inside the old wizard Gammel Dore. Neither of them could possibly predict that both of their plans would screwed up by one Cute Witch named Lillet Blann caught in "Groundhog Day" Loop.
- The Elder Scrolls V: Skyrim:
- Assuming the player never discovers the Dossier revealing the Thalmor's role in the civil war, the Dragonborn can become this for the Thalmor, who are running a long scheme to weaken their enemies by goading Ulfric Stormcloak into rebelling against the Empire and making sure the civil war goes on for as long as possible to drain both sides' strength. The Dragonborn can end the war with one of two outcomes, both of which are bad news for the Thalmor.
- In the Dark Brotherhood (Assassin's Guild) Questline, the Dragonborn can also be this for Astrid. The Dragonborn is the Dark Mother's unwitting chosen one, which screws over Astrid's position as the "family don."
- And the Ebony Blade was locked safely away in Whiterun, from champions who would be tempted into killing their loved ones and confidants to empower a stupid sword and go homicidally insane... until the Jarl's son became a talkative ass from the sword spirit's rumors. The Dragonborn figures out how to steal the sword thanks to the boy blabbing about the "woman behind the door."
- As of BlazBlue: Continuum Shift Extend, Terumi's master gambit pileup for his goals remained untouched up until Makoto Nanaya fell into one particular timeline by accident and interfered with events key to his schemes - the end result being utter annulment of all of his plans in that timeline, and she got away with it with help from Rachel Alucard. As a result, from Continuum Shift proper onward, Terumi's plans for Makoto have changed from "keep away from Tsubaki and Noel" to "outsource to Relius or kill on sight".
- This is actually a reconstruction. Makoto's Spanner status comes from the fact that she never knew Noel never existed in this timeline up until Terumi's plans had already fallen apart. Other than that, she had proven through the entire story that she was capable of picking up on the world around her and using the intel she accumulated to formulate and rebuild her plans on a whim - one slip of the tongue by Terumi was enough for her to, with help from Bang's keen-eyed disciple, figure out that Relius was luring her into a trap and adjusted her plans just enough to defuse the problem and keep at work. Had she known about that missing fact any time before she ran into Tsubaki, she could have outgambitted Terumi instead.
- In Kingdoms Of Amalur Reckoning, The Fateless One is this to everyone and everything because he/she is Immune to Fate. Furthermore, since he/she was a Blank Slate with no memories upon revival it's impossible to predict just how he/she will react in any given situation. Everyone who tries to manipulate the Fateless One for their own evil plans fails miserably. Even Tirnoch, the being that allowed the Fateless One to exist in the first place, underestimates what she created and pays for it with her life.
- The evil scheme of Pokemon Black And White goes off the rails the moment Ghetsis's Laser-Guided Tykebomb N discovers that humans aren't bastards, shaking his worldview and forcing him to reevaluate his cause, purely by encountering the player character in the second town.
- In a way, this trope can apply to the other protagonists of the Pokemon main games themselves. The villainous team's plans basically get ruined because of a person from a small town began their journey at the same time they launch their plans.
- In Max Payne 3, Max was the perfect Unwitting Pawn. A dumb gringo who'd been steered into making many enemies, he would be hopelessly lost at best, soon dead at worst. Unfortunately for the villains, good cop Da Silva showed up and gave him direction, and their plans started falling apart soon afterwards.
- In Devil Survivor 2 the Main Character can be this for Yamato and/or Polaris by choosing another faction when Yamato probably would have won if not for the Main Character's interference and possibly convince Alcor to help kill Polaris and end Polaris' system.
- In Dawn Of The Dragons, the dragons' long-running scheme to reconquer the world is derailed by two spanners. The first is a crazy wizard who wakes them up too early because he wanted to use them in his own scheme for world conquest. The second is the player character, an ordinary farmhand who frees an unborn dragon from his evil parents' influence and assembles an army alongside the newborn.
- The modern day Sonic the Hedgehog games seem to have given Dr. Eggman these moments as he'd be close to victory, then something happens that turns everything on its head. For Sonic Adventure, it's Chaos not taking Eggman's crap anymore. For Sonic Adventure 2, it's that the Eclipse Cannon had a Doomsday Protocol that activated when all the Chaos Emeralds are gathered in it.
- Tron 2.0: The F-Con CEO had been planning his takeover of Encom and invasion of cyberspace with Datawraith mercenaries for twenty years. (It's impled he was Edward Dillinger from the first film, out for payback after being forced out of Encom in disgrace). Things would have gone swimmingly...if Alan Bradley hadn't been arguing with his son Jethro at the time F-con's thugs burst in the room and kidnapped him, and if Jethro hadn't been standing in just the right spot for Ma3a to kidnap him via Shiva laser.
- In Super Robot Wars Original Generation Gaiden, Duminuss' plan was that real close to break up the spirit of EFA. First, it got ahold of Lamia and brainwashed her to the point of no return and would make her blow herself up to rub the fact that Kyosuke cannot fulfill his promise to her. That failed and later on Lamia managed to return to EFA, good as new. How? Apparently Duminuss failed to notice that that Axel just took a U-Turn from his journey to hell, and has an adjustment in personality and, being another last survivor of Shadow Mirror, he just happens to have the one thing that could reset Lamia and undo all of Duminuss' machinations, and just in case Kyosuke does not break into a world-destroying maniac out of despair (it happened in his world), Axel uses that thing pronto.
- In Baldur's Gate, the protagonist spoils Bhaal's planned resurrection as well as all the plans of three other Big Bads simply by surviving against all odds, and growing from a nobody orphan to one of the most powerful beings in the Forgotten Realms in the process. Late in Throne of Bhaal, the Solar reveals that the protagonist being the spanner in Bhaal's works has been predicted by Alaundo's prophecy.
- In Castle Red, the Big Bad, Howard, when confronted with the upcoming Trial of the Worm, set things up so that none of the other participants would even know about the Trial, allowing him to toy with them for his own amusement without risking losing his status as Lord. However, the first step of this plan was to infest all the castle's servants with worms, but he never expected that one of the servants, the maid Margaery, would be strong enough to bond with the worms and retain her sentience. This meant that there was now, unbeknownst to him, someone else in the castle who knew about the trial, knew what he really was, and who also had a vendetta against him. Once he realizes that Margaery exists and has already made contact with the other participants, he is forced to change his plans, eventually exposing himself as Lord, leading to his death at Jonathon's hands in half the endings.
- Ace Attorney:
- Kristoph Gavin's ultimate scheme in Apollo Justice: Ace Attorney was meant to be the murder of Vera Misham via a poisoned postage stamp depicting the magician act Troupe Gramarye. However, the girl is such a huge fan of the Troupe that she saves the stamp for seven years; her father eventually uses the stamp instead and dies. The flaws in Gavin's plans run deeper than this, but this is his only apparent mistake; everything else is because of Phoenix Wright's meddling.
- Larry Butz also counts, owing to his tendency to do unreasonable things that end with him stumbling onto vital evidence. In the first game, he was coincidentally returning a boat he had been using at precisely the right time to overhear a gunshot, in the third he shirked his work as a security guard when the villain's plan relied on him being at his post so that he would hear the noise of a panic button, rush into the room and arrest the wrong person and then in a later case his choice to wander around at night in the cold leads to him witnessing a number of things he wasn't meant to.
- In the fourth case of Justice For All, the lead that helps Gumshoe and company track down Shelly de Killer is, of all things living and not living, Matt Engarde's cat, who meows at the end of a transmission from de Killer.
- In the third case of Justice For All, Acro's plan to murder Regina was to call her to a specific point where he would drop a heavy weight on her head. Problem is, the note he secretly planted on Regina began with "To the murderer...". Due to Regina being very naive, she didn't think the note was for her, and posted it on the circus's bulletin board, where her father saw it and responded to it in Regina's place. Then you realize that Acro wanted to kill her because her naivete led to his brother being put into a coma, and he should have known that she would never realize the note was meant for her...
- In the final case of Ace Attorney Investigations, the shenanigans of Larry Butz and Wendy Oldbag, of all people end up helping Miles Edgeworth put away the seemingly untouchable Big Bad. Larry, by accidentally breaking the Samurai Spear, forces the staff to have the Steel Samurai use a different move instead, thus enabling Edgeworth to realize that Alba was not at the Steel Samurai show while he was killing Manny Coachen. Wendy Oldbag takes the box of "Rising Sun Dogs," which turns out to have a drop of Alba's blood on it, and combined with Alba's wound, proves that he was injured while killing Coachen.
- Larry gets to do this again in the manga. Simply by being arrested on suspicion of killing Bright Bonds (based on calling him and demanding that he get out of his ex-girlfriend's life), he derails the killer's plan to use him as an alibi, because she gets called in to prove his alibi, and through contradictions in her testimony, gets implicated as the murderer.
- In Virtue's Last Reward, Dio aspires to be one for the AB Game. Too bad for him that not only is his presence expected, it is in fact required.
- YOU can potentially become this in True Love Junai Monogatari, if you follow Ryouko Shimazaki's route. Ryouko is actually an Idol Singer (under the identity of Sonoko Takahashi) and has apparently retired, much to the sadness of her fans and the profit of her sponsors. Her manager and brother/parent figure, Tadaaki, actually had her fake her retirement to pique the interest of the fandom, then make the greatest come back ever — and since Ryouko is both his younger sister and his ward, she cannot stop him no matter how badly she wants to lead a life od her own. But after she befriends the MC, he inspires her to try speaking up and being her own self, leading her to rebel against the stage brother who controls her life and actions.
- Also, if you choose to pursue either Mayumi Kamijou or Yumi Matsumiya (who can't be romanced if you don't finish Mayumi's path first), you will also ruin Mikazaki's plan to blackmail Mayumi into sex and will give Yumi enough proof to get Mikazaki himself humiliated and kicked out of the school.
- When Tipping Forties LP'd Tales of Symphonia, they managed to go about 90 videos without using Presea, who they perceived as The Scrappy. The point was they hated the flatness of the character and refused to involve themselves with how stupid that part of the game was. Of course, they forgot the game was stupid (for that one instance, at least) and a scripted event forced them to use her. It nearly brought them to tears. And it was Hilarious.
- In the Whateley Universe, this is Jade's purpose in life. She's screwed over at least four plans, simply by being there. See "It's Good to be the don", "Christmas Elves", "Christmas Crisis", and Ayla 7-6.
- It's extremely rare for this to not happen at least once per game in Comic Fury Werewolf. It also happens intentionally a surprising amount, considering.
- Boomer, a Mad Bomber from the SCP Foundation storyline "Game Day", tends to carelessly leave dangerous explosives in random places around his hideout, to the point that it's not really possible to plan a safe approach to it.
- The "Heist" episodes of Achievement Hunter's Let's Play Grand Theft Auto V always have one that ruin their well thought-out robbery plans towards (usually) a convenience store.
- The first episode "(Geoff's) Heist" gets derailed when their explosions causes their wanted level to hit 3-star, bringing in a helicopter.
- "Gavin's Heist" goes bad when the explosives on the tanker truck they were using despawned due to distance.
- "Ryan's Heist" got derailed due to just how much trouble the gang was having trying to get the Cargobob to the armored truck.
- "Michael's Heist" hits a minor snag when he realizes that he can't rob banks yet (Rockstar hadn't added that in just yet), but recovers spectacularly.
- "Jack's Heist" gets hit because of the escape jet they were using - they couldn't escape cleanly in traffic and later roasts Michael, who had the money.
- "Ray's Heist" goes belly up because of a locked armored car door.
- "The Grand Heist" stumbles at the finish line because the Titan stalled.
- In Ten Little Roosters, Chris just can't die, preventing Burnie from getting the killer four times in a row because he keeps acting like Boromir.
- World War II
- Greece might qualify: If they hadn't held off the Italian invasion that required Germany to help them, Operation Barbarossa might have been started earlier, and the invasion of Russia might have succeeded.
- Even before surrendering to the Allies in 1943, Italy was probably as much a hindrance as a help to the Axis war effort through opening new fronts and then calling for German help. The desert war was another example, starting when Italy tried to invade Egypt from Libya and promptly collapsed to the British counterattack until Rommel arrived … which, of course, meant Rommel wasn't on the Eastern Front. At a diplomatic conference before the war German Foreign Minister Joachim von Ribbentrop sniffed to British Foreign Secretary Anthony Eden and Winston Churchill (then only an MP), "In the next war Italy will be on our side." Churchill replied, "That seems only fair. We had them last time."
- Between May 10th and May 14th, the Dutch shot down 43% of German planes deployed over the Netherlands, including 51% (220 of the 430) Junkers JU-52 transport planes. This may or may not have influenced the Battle of Britain or a potential airborne attack on the UK. The Dutch proved to be a tougher nut to crack than the Germans imagined in general. The Germans expected the Netherlands to fall within a day, which caused Hitler to issue his 11th war directive which was "The resistance of the Dutch army is stronger than expected. It must be broken as soon as possible."
- Hitler himself. If he hadn't meddled with everything, thereby wasting resources (like the V2 — great for propaganda, useless in warfare), the Germans might actually have had a chance. And that's not even counting that brilliant idea of attacking Russia. Late in the war (1944-45) this became fairly explicit: The British cancelled plans to assassinate Hitler because they believed any replacement leader would be more effective, extending the war.
- The Philippines. Even though bad luck and the Idiot Ball had ruined any chances the Filipino-American force had of successfully turning back the Japanese, the defense of Bataan and Corregidor ultimately fucked up the Japanese war plans by holding on much longer than any other Asian country aside from Nationalist China (almost FOUR whole months, from the attack on Pearl Harbor to the surrender of Corregidor. Malaya, Singapore, Hong Kong and the Netherlands East Indies had capitulated earlier). And then, there's the various guerilla movements harrying the Japanese occupiers and providing the Allies vital intelligence.
- During the Battle of Midway, the Japanese were not defeated by any cunning strategy, but because a group of lost dive bomber squadrons suddenly stumbled upon the Japanese carrier group while it was rearming all its planes, making them extremely vulnerable. This group wasn't even traveling together, it was three separate squadrons that all stumbled across the carriers almost at once, right after the Japanese fighters protecting the fleet had been drawn off by the (failed) attack run on the fleet by Torpedo 8, a squadron from the USS Hornet that had become separated from their fighter escort by poor visibility.
- Taffy 3 at the Battle Off Samar. A small collection of destroyers, destroyer escorts, and escort carriers, due to their audacity, managed to stop a force of battleships (including the giant Yamato) and cruisers in their tracks. Yamato alone had a displacement exceeding that of the entire American defense force. By all rights, the Japanese should have crushed the American defenses, opening the way to the invasion beaches and defeating a crushing blow to the American invasion at Leyte. Instead, in one of the most lopsided battles in history, Taffy 3's desperate Last Stand was so ferocious that Kurita was left believing that he was tangling with the entire Seventh Fleet and withdrew.
- One possible ally to the Axis could have been Spain, but it decided to remain neutral, in part due to its close Relations to neighbour Portugal, which decided to also remain neutral. Therefore, by not doing anything, Portugal kept the Axis form gaining another ally, Spain.
- In World War I, Germany intended to go through neutral Belgium in order to attack the French. It probably would have worked if not for the Belgian resistance delaying them. Worse than that for the Central Powers in the long run, Britain had no intention of entering the war until Germany invaded Belgium. If Britain had remained neutral, the US likely would have, as well, and it's quite probable Germany and Austria-Hungary would have won if their only sizable enemies were Russia (which collapsed in revolution), France, and Italy. Even Italy was a toss-up, as it effectively waited to see which side would give the best offer until 1915. Italian designs on Austrian territory probably gives the edge to the Entente, but without the British involved the Central Powers might have had a chance.
- On a slightly lesser note, the Portuguese intervention in the War, on behalf of Britain, started with the taking of great part of the German fleet, which was stationed in Portugal. This meant that not only they could not properly attack Britain, they could also not protect themselves against the US.
- Santa Anna's plan to finish off the Texas Revolutionaries at San Jacinto on April 22, 1836 was ruined by Sam Houston's decision to attack first a day earlier despite the Mexicans outnumbering the Texans 1,400 to 900. Santa Anna also sealed his own fate by diverting too many of his soldiers and failing to post lookouts while his army rested — not to mention supposedly getting seduced by the "Yellow Rose of Texas" Emily Morgan. The Mexicans surrendered to Sam Houston's assault after just 18 minutes of fighting.
- Developers of the perl programming language have stress-tested new versions by having it parse /dev/random as input. Bugs that had resulted in segmentation faults were discovered this way. Throwing shit at the fan and see what happens is a fairly common way of stress-testing, usually known as fuzzing.
- A Canadian fraudster used a complicated scheme involving disappearing ink and forged cheques to embezzle thousands of dollars from the banks he held accounts at. It's difficult to explain briefly, but it involved him writing a cheque to transfer funds from an account he held at one branch to the account he had at another bank. The scheme depended on his cheques being cashed at the first bank on a Friday, then the ink disappearing over the weekend, and processed at the second bank on Monday, which would give him more money in his first than was deducted at his second. Unfortunately, on one occasion the fraudster had the bad luck of dealing with a rookie teller who didn't know how the cheque was supposed to be cashed, and didn't start working on it until Monday. The boss noticed the discrepancy, accused the teller of writing the information wrong, and called the police on her. The police discovered that the check had actually been written partially in disappearing ink, and the fraudster was quickly nailed.
- Another fraudster reprogrammed a bank's computers to periodically shave ten cents off every account and apply it to the account under the last name on the list alphabetically. All went well until a Mr. Zydel opened an account and got confused as to why his bank balance kept inexplicably increasing. Zydel did the honest thing and reported it to the bank, who investigated it and had the fraudster arrested.
- "His Accidency", John Tyler. To explain: "He was a longtime Democratic-Republican who was elected to the Vice Presidency on the Whig ticket" (from his description page). As this makes him a Whig In Name Only, one wonders about his drinking habits.
- A couple of fraudsters decided to make large amounts of fake $20 bills, and in turns they bought food with those at McDonald's and other stores which worked so well they earned several thousands of dollars from the exchange money. Around half a year later they went to Las Vegas and gambled for a week without getting noticed... until one day a woman who had the weird habit of ripping the upper-left edge from the bills noticed the paper was white inside (they did not use enough ink). The couple wanted to leave but was quickly taken by security and in their apartment they had 4 four more boxes filled with fake money.
- A version from The American Civil War: on the second day of the Battle of Gettysburg, Confederate General Lee devised a strategy to attack both flanks of the Union army simultaneously in hopes of overwhelming them before they could be reinforced by the center. General Sickles from the Union ignored orders and moved his corp out in front of his fortified position to engage the enemy, a move of staggering stupidity that got his corp massacred. However, this delayed the main Confederate assault on that flank by several hours, destroying any chance the Confederacy had of launching the attacks simultaneously. As a result the attacks went on separately, and were beaten back separately. This in turn led to Lee gambling desperately with Pickett's charge the next day, a disaster that effectively destroyed Confederate momentum in the war. While people often "what if" this battle, it is pretty generally agreed that Lee did not do a very good job of commanding the battle in general, and there were far, far more problems than this one.
- Thomas Blood's plan to steal the British Crown Jewels failed only because the elderly caretaker's son came back on leave from the navy at precisely the right moment. Seriously.
- Vanessa Williams thought she'd never be able to live down the nude photos that appeared in an issue of Penthouse and cost her her Miss America title. Then it was discovered that the centerfold was underage, and the issue was banned along with most of the centerfold's filmography up to that point (with the exception of Traci, I Love You) as well as the porn industry ostracizing the centerfold in question entirely. Williams was supposedly relieved to see all those nude photos of herself go bye-bye over an underage centerfold appearing in the same issue as said photos.
- This happened to Tennessee in their 2010 college football match against LSU. UT had the game won when LSU stupidly didn't have a play ready for a third-and-goal with seconds remaining and no timeouts, resulting in a botched snap that looked to end the game. But UT trumped it with their own stupidity in a last-second personnel change that resulted in Two Many Volunteers on the field (four guys came on while three ran off, and then one of the three ran back onto the field). The illegal participation penalty forced the down to be replayed (American football games can't end on a defensive penalty), giving LSU time to settle down and organize the game-winning play. You can watch the last moments of the Dumbass Miracle here.
- Related to sports, Bill Simmons' "Levels of Losing" have as the seventh "The Monkey Wrench", where a bad decision by either the coach or the umpire costs the victory.
- Political parties in America are this, believe it or not. The government was set up so that all three branches—executive, legislative, and judicial—would be more or less in opposition to each other. The rise of political parties put an end to that in a hurry. Indeed most of the founding fathers were completely against political parties, but viewed them as a necessary evil that would naturally arise despite their best efforts.
- In Major League Baseball, you have the Steve Bartman story. In 2003, the Chicago Cubs were a very good team whom many picked to win the World Series (and finally break the Curse of the Billy Goat). And during the National League Championship Series against the Florida Marlins, it seemed like this would be a reality. The Cubs built a 3-0 in Game 6 and ace pitcher Mark Prior was retiring batters with ease, working a three-hit shutout through the first 7 1/3 innings. Then Marlins shortstop Luis Castillo hit a deep foul ball that sailed towards the edge of the stands, a ball that Cubs outfielder Moises Alou had a shot at catching for the second out of the inning. Instead, a Cubs fan (Bartman) interfered with the play by reaching out his hand to catch the ball. This angered the Cubs (Alou was very visibly frustrated after the play), who complained to the umpire for a fan interference call. The umpire ruled against them, stating the ball had left the playing field when Bartman touched it (if it hadn't, Castillo would have been called out). The most upset was Mark Prior, who completely lost his focus and began giving up hit after hit. He was taken out of the game and replaced, but the relief pitchers, also unfocused, gave up nothing but walks and hits. The Marlins scored 8 runs in that single inning, and ended up winning that game, Game 7, and eventually the World Series that year.
- The 9/11 attacks could have been much worse if not for a major spanner. Four planes were hijacked; one was probably intended to crash into the White House. However, the terrorists did not take into account the passengers attempting to retake the plane. The aircraft crashed a hundred miles or so from its target, and although lives were lost, it would have been far worse if the White House had actually been hit.
- In a story from Not Always Working, some video game store employees inadvertently thwart a shoplifting scheme in the process of setting up a prank.