"While most agree that the financial theory behind the scheme is 'crazy,' others counter that the idea of flying a hot-air balloon filled with dry ice over Wall Street is so outside the realm of conventional thinking that, paradoxically, it just might work."
In real life, when someone is in serious trouble, they, even on the fly, have to think of a logical, sensible and reasonable strategy that can get them out of it with as little loss as possible, in the best conditions possible as well.
In movies, the characters can make the most irrational, nonsensical or plain dumb decisions, and it works!
Because it's Crazy Enough To Work, that's why. Sometimes characters will even credit it to it being crazy (enough to work). A possible example would be something along the lines of "What about patching up the nuclear reactor with a pack of gum and peeing on the fire from the top of the reactor? That's so crazy, it just might work!"
While heroes of every genre will come up with these, expect a lot of them from Badass Unintentionals, since they lack the knowledge, strength, and sometimes even the courage to come up with a better idea.
Lampshaded frequently enough that it's become a Stock Phrase of the Genre Savvy.
Routinely pulled off by Crazy Awesome characters. Compare Million-to-One Chance; the less probable a plan is to work, the more likely it will succeed in Hollywood conditions. See also It Runs on Nonsensoleum and Refuge in Audacity (which run on a similar premise) and It Will Never Catch On (which is a specific type of joke that invokes a similar reaction in the audience). See also Confusion Fu for people who weaponize this trope.
If smashing a small robot into a big robots head, almost impaling the pilot of the big robot (who, by the way, was the one who thought of this) in the process is not Crazy Enough To Work, then nothing is. Oh, and they also run a walking, nonflying battleship up a mountain and jump through the air for a good half a mile just to get a chance to kick an Airborne Aircraft Carrier. This universe runs on Rule of Cool, so it was destined to succeed.
And when the flying kick only scratches the side of the Airborne Aircraft Carrier? They at once make the captain fling the wheel over in the most exaggerated way possible, turning the flying kick into a flying roundhouse kick that of course succeeds.
Everything that happens in Gurren-Lagann is too crazy to work. And yet it does... Their universe operates in these rules, seen as at some point there are literal giant robots piloted by giant robots!
Bleach: In episode 135, we see Matsumoto, with Kon by her side, saving the life of a girl that was about to drown when falling in the water after her plushie. How? By removing Kon from his plushie body and tossing him in the mouth of her plushie, to get Kon—as the plushie—to go save the girl instead of, say, going in there herself. She offered a weak rationale ex post facto, and simply let the hilarity ensue.
In the early episodes of Black Lagoon when their torpedo ship is cornered by an attack chopper the 2 badasses and the tech nerd onboard were getting ready to kiss their asses goodbye when the timid loser businessman they had taken hostage comes up with a plan to charge the copter head-on and use a shipwreck as a ramp to launch them high enough that they can hit it with a torpedo. It works, of course.
Isaac and Miria in Baccano! usually get away with their crimes because they are so absurd that no-one can take them seriously, or believe that they could pull something like that off. For example, they robbed a Mafia money delivery dressed up as Babe Ruth and Ty Cobb, and knocked out the wise guys with baseball bats in the middle of the day on an open street only a few yards from their office.
Mazinger Z: Kouji's plans CAN be carefully and throughtfully planned strategies, but many times his plans are an Indy Ploy or... this. One example happened in episode 32: Mazinger Z got the crap beaten out of it by Gelbros J3, a flying, three-headed dragon-looking Mechanical Beast. Mazinger could not fly -yet-, so Kouji could not fight back. His plan was... equipping Aphrodite A with even bigger Torpedo Tits. During the battle Sayaka shot them, Mazinger latched on the giant missiles and was propelled it skywards, where he was capable to reach the Robeast and shooting it down.
In the Dragon Ball anime-only ending, Goku and Chi-Chi have to scavenge to find the magic Bansho Fan when the couple and the master's Turtle come across a book by Kame Sen'nin detailing the instructions on how to build one. Although the master later berates the Turtle because he was drunk when he wrote it, the scavenge does lead them to the Fan and its original purpose (to fan the Furnace of Eight Divisions). The scattered elements of Kame Sen'nin instructions were actually on the right track, but their ultimate purpose was misguided.
After a completely even fight, Goku gives up on fighting Cell and makes Gohan take his place in the fight. Everyone reproaches Goku for making his own son do such a thing and it takes Piccolo's admonishment to make him realize that Gohan is not driven to fight as Goku is and that he was mistaken in doing such a thing. Albeit it does work, as Gohan ends up being strong enough to overtake Cell ultimately (twice), it ends up costing Goku his life in an effort to defeat him.
In the Buu arc, much of the behavior and actions of Goten and Trunks (and Gotenks for that matter) are fueled by this.
Getter Robo: Practically the Getter team lives -and survives- on it! Ryoma usually comes up with some absolutely crazy maneouver and his teammates simply go along it. And it works! One example (from Getter Robo G) was when they trapped a flying Mecha Oni by allowing it impaling their Humongous Mecha.
If there's anybody who is able to get more powerful from perversity, it's Issei Hyodou. Seriously, almost every single power up he has involves Rias' breasts or the breasts of his harem. Some of these include: Clothing Damage to a female enemy and bombarding them with powerful attacks, hear breasts talk and it will only tell the truth, and use Rias' breasts as a battery source.
How about using that very Clothing Damage ability to rescue Asia from becoming a Nuke?
In episode 12 of Girls und Panzer, the Oorai girls Tankery team runs into a gigantic Maus tank. It promptly knocks out two of their tanks with little effort, and forces them to retreat. Saori reads up on it, then laments that its like a tank on top of a tank. Which gives Miho a crazy idea based on what her friend just said. They have one tank go underneath it to prevent it from moving its tracks, then a smaller tank on top to prevent them from turning their turret, then Miho's tank knocks it out by shooting at one of its exposed grills.
The "Daedalus Attack" in Super Dimension Fortress Macross. It involved the titular ship covering its right arm (which was a submersible troop transport ship named the Daedalus; long story) with Deflector Shields, then ramming it through an enemy ship's hull, opening ports once inside and firing missiles all over the place. In other words, the giant mecha spaceship punches an enemy ship and then makes it explode from the inside. It was basically a desperate, last-ditch tactic thought up when the Wave Motion Gun was down, but it was so effective that they end up re-using it several times throughout the show, and it even makes appearances in later series on occasion.
In the finale of Superior Spider-Man, Spidey attempts to reconcile with Miguel during the finale, he tells him the honest to goodness truth, that "It was Doc Ock mindswiping with me" along with everything else. Miguel points out that it's so stupid that it has to be true and all is forgiven.
Company0051 has grenades taped onto dodgeballs. Granted, it'd just be easier to throw the grenades themselves, but it does allow the Kid Soldiers to show off their mad dodgeball skills.
Paper Mario X Chapter 54: "Hmm…that's crazy enough to work!" pondered Samus.
Every single one of Takato's plans in the Tamers Forever Series and I use the word 'plans' in the loosest possible terms. .
The whole plot of Decks Fall Everyone Dies is to pull off a plan that's so crazy it might work to bring card games back.
Chapter 81 of the Halo fanfic The Life involves the protagonists team dropping without him. He convinces the captain of the ship to do a flyover near the position of his squad. He jumps from the cargo bay of a frigate with a jetpack that he doesn't know how to use and a tank with parachutes attached to it. While playing "Iron Man" by Black Sabbath on the helmet's speakers.
Mom: Well, that's nice, but you don't need to broadcast it coast to coast! Just look for him (Hobbes) quietly.
Calvin: Of course! If I continue to shout for him to show up, he'll know where I am and get farther away from me! On the other hand, absolute silence means absolute secrecy! It's so crazy it just might work!
In NGE: Runaways Misato needs to come up with a plan to break Rei out of Nerv while Shinji escapes to rescue Asuka. Something all but impossible. Then she says: "You know, this might be total madness, but I actually might have a plan..." What is her plan? Later we find out:
Rei: "Are we stealing an Evangelion?"
Misato: "Yes we are, because we are insane."
In Vengeance from the Grave Harry suggested that a couple of his fellow Unspeakables deal with several giants using their Animagus forms by having the panther slash the giants' Achilles tendons after which the bull would push them over. The team leader commented "That's just stupid enough to actually work."
From Bajor to the Black: Kanril Eleya takes out a Borg probe by charging it, neutralizing its shields with those of her own ship, and beaming a photon torpedo aboard, then running like hell before the torpedo blows.
Captain Jay Yim: Lieutenant Kanril, are you insane?! Eleya: It worked, didn't it?
Argo: Lampshaded In-Universe by one of the hostages after hearing about the plan to pretend they're Canadian filmmakers to sneak them over the border. "Is this the part where we're supposed to say this is so crazy it might work?" (and given it's a true story...)
Ordinarily, when a mining ship from the future commanded by an Ax-Crazy Romulan shows up and starts laying waste to ships and planets, most folks would decide to steer clear of the damn thing. Of course Captain James T. Kirk decides that the best course of action is to take them head on.
When Jack Sparrow uses the recoil of a cannon to toss him from one ship to another, it prompts the exchange between him and Lord Beckett:
Lord Beckett: You're mad! Jack Sparrow: Thank goodness for that, 'cause if I wasn't this would probably never work.
And upon landing in front of his bewildered crew:
Jack Sparrow: And that was without even a single drop of rum!
In the first film, the Black Pearl is closing down on our heroes. Since they've already thrown the ammunition overboard in an attempt to lighten the ship, Will orders the crew to make a stand and fight, loading the cannons with anything they can find. Then, when it becomes clear that the Pearl will catch them before they can even try to fire on it, Elizabeth tells Anamaria to club-haul the ship, an extremely risky nautical move.
Lando had one in Return of the Jedi when he commanded the Rebel fleet to attack the Imperial Star Destroyers at point blank range, guessing that A. The Death Star wouldn't fire on them for fear of taking out the Imperial ships in the process, and B. The Empire would actually think the Rebels knew what they were doing more than they let on (This was elaborated on further in the novelization).
The basis behind the plan to rescue Morpheus in The Matrix. Complete with call out.
Trinity: Nobody has ever tried anything like this before. Neo: That's why it's going to work.
Parodied in the Dana Carvey film The Master of Disguise. The line is repeatedly used for the most simple and straightforward plans. Dramatically.
Iron Man: Okay, so you're a rich playboy snarker who's out for a relaxing afternoon drive in the deserts of Afghanistan, when a bunch of psycho terrorists blast the crap of your armored truck, fill your chest with shrapnel, hook you up to a car battery, toss you in a cave, and then tell you that if you don't make a missile for them, they're gonna feed you to the hyenas. Sounds like you're screwed, don't it? Here's what you do: build a tiny chestplate that puts out more energy than the warp core of a Federation starship, forge some iron and heavy metal by hand, and design a badass suit that's capable of kicking doors off hinges, bitch-slapping terrorists by the dozen, equipped with a rocket launcher, a pair of flame-throwers and has a rocket pack so that you can blast off after wreaking havoc. Oh, and you have to do this while trapped in a terrorist bunker being monitored 24/7 on camera. Most people don't have the audacity to attempt something so brazenly outrageous. But then, Tony Stark ain't most people!
Willie Scott:(sees Indy raising his sword)Oh my GOD! Oh my god, oh my god, oh my GOD, is he nuts?!
Short Round: He no nuts, he's crazy.
The Lord of the Rings: The Return of the King: They're about to suicidally attack Sauron's far superior army to distract him while Sam and Frodo try to complete their insane plan of attempting to simply walk intoMordor, somehow bypass the tens of thousands of bloodthirsty orcs, climb up an active volcano barefoot, and destroy a telepathic Artifact of Doom before it takes over their minds and/or gets stolen from them and handed to Sauron, which would grant him godlike power. Not only does it work, but all the heroes survive, except for Gollum and a bit of Frodo.
Gimli: Certainty of death, small chance of success... What are we waiting for?
Sahara: Pulling a Panama? Okay, believable, considering gas is just as flammable today as 2005. But using a box of tools to convert a one-winged, at-least-as-old-as-you airplane into a windsurfing desert-crosser? Really? That's actually pretty standard for Dirk Pitt.
Ghostbusters had this when Egon suggested that they cross the streams to defeat Gozer.
Peter Venkman: I love this plan! I'm excited to be a part of it! Let's do it!
Parodied in the film adaptation of Sgt. Bilko when Steve Martin's title character utters a variation of the Trope Name upon learning the new recruit to his motorpool division actually is a trained mechanic. "A real live wrench-turner in the motorpool? It's so crazy it just might work!"
The comedy Down Periscope centered around an officer being tasked to test the abilities of the US Navy to adapt to unconventional warfare because he had a tendency to think this way.
Seaman Sylvesterson: Actually, sir, I think we prefer to go with the bizarre and risky. Worked for us so far
From Guardians of the Galaxy: Big Bad Ronan The Accuser is about to use the most powerful weapon in the galaxy to destroy a planet. So what does Star-Lord do? Challenge him to a dance-off, completely bemusing Ronan and distracting him for long enough for Rocket to MacGyver a gun, knocking said weapon (a infinity stone) away.
Ronan: "What are you doing?... What are you doing?
Star-Lord: "I'm distracting you, ya big turdblossom!"
What do you do when some of your enemies have survived your flaming deathtrap and are beginning to storm up towards your capital city from your shores - oh, and the leader of your men refuses to go near them, as he's suffering severe post-traumatic stress disorder from being set on fire himself in the past? Oh, and you're a dwarf who can't even walk properly? Say "to hell with this" and lead the charge yourself, shaming nearly everyone else into following you. What happens when your enemies on land are all vanquished, but some of the ones from the flaming ships are leaping across the wreckage, swords at the ready? Meet them on the wreckage in single combat, getting your face horribly scarred in the process while you nearly drown.
Also, any desperate plan Daenerys ever makes, especially the ones involving dragons or their eggs. Copycats aren't so lucky.
Animorphs invoked this frequently pretty much every time Rachel came up with a plan it was this. Marco says it word for word more than once. What to do when one of your friends has been kidnapped, held prisoner in a ridiculously well-guarded underground base, and you have less than two hours to rescue them, all while your leader isn't even around? Impersonate a jet pilot, steal a jet, fly it straight down into the ground through a building, then bail out and jump into battle. Even then, it only worked because they made the Big Bad's day when they killed a political rival in the process, and he didn't bother to stop them from leaving the mess. Rachel, folks.
Discworld: 'It's a commonly known fact that million-to-one chances happen nine times out of ten.' It has to be exactly a million-to-one chance though.
Sergeant Colon looked wretched. "Weeell, what if it's not a million-to-one chance?" he said.
Nobby stared at him.
"What d'you mean?" he said.
"Well, all right, last desperate million-to-one chances always work, right, no problem, but...well, it's pretty wossname, specific. I mean, isn't it?"
"You tell me," said Nobby.
"What if it's just a thousand-to-one chance?" said Colon agonizedly.
"Anyone ever heard of a thousand-to-one shot coming up?"
Carrot looked up. "Don't be daft, Sergeant," he said. "No one ever saw a thousand-to-one chance come up. The odds against it are—" his lips moved—"millions to one."
"Yeah. Millions," agreed Nobby.
"So it'd only work if it's your actual million-to-one chance," said the sergeant.
"I suppose that's right," said Nobby.
"So 999,943-to-one, for example—" Colon began.
Carrot shook his head. "Wouldn't have a hope. No one ever said, 'It's a 999,943-to-one chance but it just might work.'"
The majority of plans crafted by Codex Alera's hero, Tavi of Calderon, hinge on this. So much so, in fact, that his lover is able to correctly reason Tavi's chosen location for the series Final Battle by thinking of a place that only a lunatic would willingly enter.
You want examples? Of course you do! Take, for instance, his role in the defense of the Elinarch. Due to a lot of things going wrong at once, he ended up in command of a single, inexperienced legion (about 7,000 soldiers) who had to hold a bridge against an army of more than 50,000 Canim: centuries-old, enormous, and incredibly dangerous wolfmen. First, to stop them from crossing the river anywhere else, he had all the butchers in the camp and the towns at either end of the Elinarch throw buckets of blood into the river to attract sharks. Any Canim trying to swim across quickly learned the error of their ways. He also went out to try to negotiate with the leaders. By himself. He proceeded to use his knowledge of their culture to laugh in the face of an Evil Sorcerer and exploit a division in their leadership. Then he sat for an hour and played chess with Nasaug during a truce to let them remove their dead from the fieldnote Tavi won, in order to buy time for his men to set up his next tactic: sawdust and fire furies planted in every building on the Canim side of the bridge, which he then had his only Knight Ignusblow up while the Canim were trying to move through them. He'd made sure they were all in the buildings by having everyone in the legion hold tiny firecraftings over the main square so the stones were superheated and anyone trying to step on them would get fried. And the battle ended when he had his Knights Aerisbend the air to form a quarter-mile-wide magnifying glass, concentrating the sunlight into aDeath Ray. The general consensus among the characters seems to be that Tavi is completely insane.
Ehren: "This plan is insane....You are insane....*looks around* I'm going to need some pants.
And that thing mentioned above about going into the most suicidal place he could think of? His plan was to piss off the Eldritch Abomination-like Great Furies Garados and Thana and use them against the Vord Queen. It only really works when she tries to claim the furies and he has the even crazier idea of cutting her connection and letting them go free to wreak random destruction. They are very pissed about the attempt to control them, and Thana, an enormous, sentient thunderstorm, pretty much literally chews the Vord Queen up and spits her out.
Harry's plans in The Dresden Files are often of this variety. Since they are written by the same man as Codex Alera, this is far from surprising. Zombie Tyrannosaur, anyone?
"Challenge everyone (White Council, White Court, Shagnasty) who shows up in one place at the same time, just to try to draw out a single baddy who won't be able to miss the opportunity". Particularly since the thing that worked in the end was hiring a plain old vanilla mortal private investigator to take pictures of everyone going through the Ways to the island. And then presenting his dog (a magic temple dog at least as smart as a person, admittedly, but still a dog and not capable of speech) to corroborate the photo evidence.
Drinking a magical Klatchian Coffee, jumping out of a moving car and facing down a group of psychopathic lycanthropes at full moon. And this isn't the craziest thing he has done.
Possibly the craziest - or at least the riskiest - was in the third book when one of his plans hinged on deliberately ingesting lethally poisonous mushrooms.
Thomas: I thought you were lying. Bluffing.
Harry: I don't bluff if I can help it. I'm not too good at it.
In Cold Days:
Karrin: You want me to drive into the lake. Harry: You have to admit, it isn't the craziest thing I've ever asked you to do. It isn't even the craziest thing I've asked you to do tonight. Beat Karrin: You're right. Let's go.
John: I'm lead, Jim is rhythm, Jen sings backup. Jen, just repeat everything Dave sings, only like one second behind. The sound system will be on the stage. We duck out there and plug in and wail. Okay? Guys, this is just retarded enough to work.
X-Wing Series. Wraith Squadron specializes in these plans. Just during their first active mission, they fake the Millenium Falcon to decoy a Star Destroyer away from an evacuating Rebel base then proceed to capture(and utilize in a False Flag Operation) a Correlian Corvette pocket carrier with an X-wing's laser cannon carried by the squadron's resident Gamorean.
Kelsier of Mistborn pretty much can't go a single chapter without someone saying he's nuts, usually because of the sheer, ludicrous Refuge in Audacity. His plans usually work for exactly that reason.
In A Hymn Before Battle, during the events of the defense of Diess, Lt. O'Neal had acquired a reputation for plans that sounded crazy but were thought to possibly work, due to the successes of his unconventional campaign against the Posleen.
Early in The Rising, Commander Peter Raeder drives a Space Pirate fighter away from a damaged freighter by landing a repair scooter on it and bashing its sensor arrays to pieces with a hammer and a set of tin snips. As he runs the heck away, the pirate radios its buddies that the Merchant Marines have developed a new weapon of some sort. (Raeder had a fun time explaining that line to Intelligence.)
In Small Gods inhabitants of Ephebe believe that crossing the desert is impossible, so they keep all their military forces focused on the sea. Vorbis sends several caravans to leave supplies along the way, which lets Omnian soldiers cross the desert and take Ephebe completely by surprise.
Live Action TV
On The Knick, Dr. John Thackery needs to perform surgery on a man with bronchitis, meaning that he can't be given ether. His solution? Inject cocaine into the man's spine. In-universe, this procedure has only ever been tried once, on a dog. And the dog died. His colleagues think he's insane but, obviously, it works perfectly.
This is deconstructed in the season one finale. Thackery once again performs a revolutionary new procedure on a patient but this time he kills the patient. He drew incorrect conclusions from his research and he was too stuborn and paranoid to consult with other experts in the field. In addition, the patient's life was in no immediate danger so there were no extenuating circumstances to justify him performing such a risky experiment on a patient without her consent.
Pick any (and we do mean any) of the plans hatched by the folks on Stargate SG-1.
Blowing up a sun; using every Stargate simultaneously to generate a wave capable of disintegrating matter across the whole galaxy.; sneaking into a conference where all your major enemies are gathered; storming an enemy mothership with just four people. Believe it or not, these aren't the craziest ones.
One later season episode lampshades the escalating ridiculousness:
Col. O'Neill: All I'm saying... just for the record... this is the wackiest plan we've ever come up with. [He turns and starts to leave the room] Maj. Carter: Wackier than strapping an active Stargate to the bottom of the X-302? Col. O'Neill: [As he walks out the door] Oh, yeah. Maj. Carter: [Calling after O'Neill] Wackier than blowing up a sun? Col. O'Neill: [From the corridor, unseen] Yep! Maj. Carter: [to Jonas and Daniel] ...He's probably right.
Some of the stuff that Chuck Bartowski comes up tests the very limits of sanity. But somehow, it works. There are reasonswhyitworks.
Farscape: See John. See John have a fight with a large empire. See John strap a nuclear bomb to his chest and walk into their headquarters as a diversion. See John Win.
A fair number of Star Trek adventures feature somebody coming up with plans that are Crazy Enough To Work.
Scotty especially had a habit of making stuff work that simply defied the laws of physics. Subverted for some darn reason, later, in which we learn that sometimes Scotty exaggerated the time limits to make himself look awesome. No exaggeration, just a good engineering practice of being conservative in your tolerance specifications. You don't want to run the ship at redline the whole time.
As mentioned above, James T. Kirk is the patron saint of Crazy Enough To Work. From corbomite to fizzbin, most of his plans are completely insane when viewed from a distance.
Played with in Star Trek: Voyager. Former Maquis, who made up a lot of the crew, had to make do with next to nothing a lot, so they came up with ways to do the mission that'd make regular Federation officers protest like mad. Janeway was smart enough to let her Maquis people do their thing when needed, but even then it didn't always work.
Many of the myths tested on Mythbusters turn out to be this. For example, if a car goes fast enough, can it skip right over the surface of a 120-foot lake and keep driving when it gets to the other side? The Build Team didn't think so either. Then they tested it. Can you fool a highly-sensitive sonar motion detector by holding up a bedsheet in front of you to absorb the sound waves? Guess what...
Every single episode of MacGyver, of course. Crazy Enough To Work is the driving principle behind MacGyvering.
Hogan: Well, we've got to stop Williams, but use him as a diversion so we can knock out that gun.
Newkirk: With all due respect, sir, you're dreaming.
Hogan: If you've got a better dream, I want to hear it.
Boy Meets World has an episode where Shawn tries to escape Cory's house through his bedroom window which leads out to the backyard. The problem is, the parents are out there. After freaking out for a minute, Shawn is reminded by Cory that he could just go out the front door. Shawn questions this for a second, and then states that it's crazy enough to actually work. It does of course.
Colonel John "Hannibal" Smith: It gets better! (starts laughing)
Corner Gas. Many of the schemes tried by Brent LeRoy and Hank Yarbo (and a pretty significant chunk of the schemes everyone else in the main cast try) fit into this trope. Most of the time the plans fail miserably, but even when they work, the success just creates another problem they hadn't anticipated.
This happens a lot in Blackadder, always prefaced by the words "I have a cunning plan". Subverted as these plans usually fail, or are so stupid that is no way to actually enact the plan. "Pathetic! Absolutely pathetic! Contemptible! Worth a try!"
On The Daily Show, when John Hodgman (Resident Deranged Millionaire - no, really, it's his actual title) suggests that America fake its own death to avoid debt, Jon Stewart said "Wow, that's so crazy... it just might be fucking crazy."
Any and all prison escapes by Michael Scofield of Prison Break. Features of his plans include structural engineering know-how, coded phrases and last minute improvisations due to being failed and/or betrayed by other people. However special mention must go to his later plot to steal Scylla. Let's take the most prized possession of the powerful Company that keeps trying to torture and kill us!
Doctor Who runs on Crazy Enough to Work, but even they outdid themselves with the grand plan to save Gallifrey in "Day of the Doctor". The Doctor(s) plan(s) to use the TARDIS(es) to trap Gallifrey in a single instant in time and store it in a pocket universe, hiding from the rest of the universe and allowing the Daleks who have the planet surrounded to blast themselves to smithereens. The Time Lord General's reaction to this is priceless: "I'm sorry... WHAT!!??
Major Bunny Colvin comes up with a pretty interesting plan in season 3 of The Wire. Faced with the drug trade sprawling over more and more of his streets, as well as an increasing pressure to get crime rates down, what plan does he come up with? Legalize drugs. More specifically, he sets up three "safe zones" in his district and makes a deal with the dealers: if they move all their trade there, the police won't touch them. And it works. Dangerous street corners are cleared for ordinary people and his men can focus on fighting crime more concretely, as opposed to making endless futile drug raids. Crime goes down 14%. But in the end, The Wire is too naturalistic for such a Zany Scheme to be workable: once his superiors find out about the whole thing, "Hamsterdam" is shut down, Colvin is disgraced and the streets return to normal. Major Rawls even comments that his plan was brilliant - insane and illegal, but brilliant.
Angel. The plan to capture Angelus has to qualify. It involved Faith doping up during a fight, allowing herself to be fed on, then Angelus getting high off the drugs she took.
Firefly The crew of Serenity practically does this for a living. The maneuver "Crazy Ivan" is called that for a reasonnote This reason has less to do with this trope and more to do with Cold War Soviet subs playing sonar tag with their NATO counterparts, jumping onto a moving train is risky enough when it's not a hyper-fast futuristic train, injecting yourself with adrenaline to stay conscious long enough to call for help can be suicide, fighting off about thirty seasoned fighters with a bunch of prostitutes needs no explanation, and even Jayne didn't think it was possible to get Mal out of Niska's skyplex.
A rare serious version occurs in the season 3 premiere of Falling Skies:
Pope: So you think we can just sneak in from behind and take the Espheni by surprise. Well, that's insane.
Weaver: Which is exactly what the enemy thinks. Which is why they have left the back end of the plant undefended.
One Zits storyline started off with Jeremy volunteering to work as a receptionist at his Dad's office for a bit. Walt says it's just crazy enough to work while Connie only agreed with the first three words of that line. It did ultimately work out.
Destroy The Godmodder: Lots and lots and lots of these. Enemy not taking damage from guns and swords? Hit him with a chair. The godmodder deflects nukes? Throw a nuclear snowball. Giant universe eating demon with infinite health? Burn his overcoat.
In Halo 2, the Master Chief dives out of Cairo Station with a bomb larger than himself and falls into the engine of a Covenant Carrier, detonates the bomb, and falls again to land on a UNSC ship that is miniscule by comparison.
Cortana: I know what you're thinking, and it's crazy.
Master Chief: So? Stay here.
Cortana: Unfortunately for us both, I like crazy.
Sarge: For a brick, he flew pretty good!
In Halo: Reach, Kat proposes a way to take out a covenant super-carrier that involves "the single most expensive piece of equipment made by man".
Carter:"Even for you, Kat, that's..."
Carter:"Not the word I would use."
Subverted in Fire Emblem: The Sacred Stones. Ephraim, along with his 3 bodyguards, plans to raids the enemy castle and take it over, on the basis that "If the enemy thinks the same [that the plan is insane], there's our opening." Unfortunately, it turned out that one of the aforementioned 3 bodyguards was The Mole, and therefore the enemy was completely prepared for the siege.
In Tales of Vesperia this is intentionally invoked when Brave Vesperia formulates the best way to destroy the Adephagos by using Spirits and the removal of blastia from the world, something that would be all but impossible. However, it works, and the world is saved.
It works partly because your character, the best fighter in the group, went along slaughtering guards and setting the city on fire just a few minutes ago. In the smoke and chaos, no one looks closely enough at your party to realize they're groups of three humans playing Neferset horsie ride. You'll notice that the next time your character canonically enters the city, they've stepped up the guard patrols quite a bit.
In Crysis 3, Psycho says that going straight through the front door into the Liberty Dome will work because it's so crazy that CELL will never see it coming.
This trope sums up Laguna Loire's plan to defeat the Big Bad of Final Fantasy VIII, an Evil Sorceressfrom the future whose consciousness possesses people in the present and is trying to compress time into a singularity in which only she can exist. Since they can't touch her in the present, what is Laguna's plan? Give her what she wants, so that a team of combat specialists can get to her through compressed time and kill her, then rely on the Power of Friendship to get them back to the right time when the timeline decompresses. Squall, the leader of the team, tells Laguna up-front that the plan is ridiculous, but goes along with it anyway because it's still their best shot.
Annyseed uses a love potion in order to deter someone from her, rather than attract someone to her. Winston, you’re a genius! Mmwa! Page 61.
So many things in Sluggy Freelance. One of the best examples is the Ferret Bazooka, where Caffeine Bullet Time is weaponized by putting a hyperactive ferret in a cardboard tube, pouring in a pixie stick, then pointing the tube at whatever you want destroyed. If all goes as planned, a ferret on a serious sugar rush will shoot out of the tube at supersonic speeds.
Parodied in xkcd. When Nathan Fillion wants to try the Crazy Ivan maneuver from Firefly on his electric skateboard, he insists it's so crazy it has to work. Jewel Staite replies "No, that's the opposite of true." She was right.
Alt Text: "Things are rarely just crazy enough to work, but they're frequently just crazy enough to failhilariously."
When they try to mimic what Jim would do, Annie keeps doing things to try to slow half of a spaceship's fiery descent from orbit. Each time, Pete responds with "Not crazy enough!" Finally, her plan is to fire all of the ship's missiles at the ground just before landing, using the explosion to cushion the fall. Pete's response? "Too crazy!" It works.
About half of Generator's plans in the Whateley Universe. Of particular note is her plan to defeat the killer simulation they were given at Whateley Academy. Three words: Radioactive Condor Girl. Not only was it crazy, but it worked so well the simulation staff banned the technique. Her Hello Kitty makeup compact that is also a flying attack weapon might count too, along with her stuffed cabbit. Which she weaponized.
Twilight:That's all you know [about Pinkie Sense]? Applejack: Well, if you want, you can just try asking her. Twilight: That idea isn't crazy enough to "just might work"! [14 hours later...] Twilight: Pinkie, can you tell me how your Pinkie Sense works? Pinkie: Yeah, okay. Twilight: I can't believe that worked!
One Tiny Toon Adventures episode has Babs and Buster consulting a computer on how to rescue a friendly flea living on Furball from an evil, carnivorous bug. The computer reads, "Cliché #1: Shrink our heroes." After Babs says it's crazy enough to work, Buster says "That's Cliché #2!"
On Family Guy, Peter says this before putting his hand in a waffle iron. Needless to say, that didn't solve the problem at hand. However his second one does. But it caused a problem at hand.
Spoofed in one episode of Sponge Bob Square Pants. Patrick suggests moving Bikini Bottom to avoid an attack from a giant worm. Squidward says, "That idea may just be crazy enough... to get us all killed!" They do it anyway. And it fails. It's worthy of note that the only reason it failed is because the worm was lured over the cliff the city was pushed under.
In Kim Possible, Shego says of a plan by Dr. Drakken, "I know I'm going to regret saying this, but I think you may have finally achieved 'so dumb, it just might work.'"
In an episode of Futurama, the Planet Express crew and the Globetrotters are trying to solve the problem of "time skips" that jump everyone in the Universe forward in time, leaving them with no memory of what went on in the interim. At one point, Hermes Conrad says, "Say, I'm no physicist, but I think I know how to stop the skipping. We'll just—" after which time skips, everyone but Hermes is nude and in a conga line (Hermes is in a Hawaiian shirt, playing a steel drum) and Hermes cries, "I don't know how this was supposed to work!" Of course, most of the (often successful) plans in Futurama — especially if they're by Farnsworth or Fry — are usually Crazy Enough To Work.
Carl: Johnny, I have a plan. Johnny: It's just crazy enough to work! Carl: But you haven't heard it yet. Johnny: Enough talk! I need action!
Beast Wars. After Optimus Primal jumps, in beast mode, from a flying island that's just more or less gone nuclear, in the hopes of catching a tree branch on the way down before he and Rattrap go splat or get charred to a crisp. He does.
Rattrap: Of course you do know that was crazy. Optimus Primal: Sometimes crazy works.
Jumba: That's crazy! Lilo: So crazy it just might work, right? Jumba: No, just crazy.
Used often in Hey Arnold! Usually with the phrase, "That's the stupidest idea I've ever heard. Let's do it!"
Played with in Maryoku Yummy when Maryoku and Shika are searching for Bob. Shika starts out by systematically checking every spot in Nozomu, but Maryoku suggests starting with the places they'd usually find Bob.
Shika: Well, it sounds crazy, but— Maryoku: Good! Follow me! Shika: But I said it sounds crazy! Maryoku: Yet you're still going to give it a chance. That's so nice.
Used almost word for word in an episode of the 2010 Pound Puppies:
Strudel: An adoption fair? How crazy is that? Lucky: So crazy, it just might work.
Parodied in Drawn Together. When Spanky fills in every blank in a mad-lib with "Penis", Wooldoor suggests using words other than penis, to which Spanky replies "That's crazy, Wooldoor! Just crazy enough to penis."
One episode of Megas XLR (itself a big parody of sci-fi and anime clichés) found the titular robot with a critical part badly damaged, so they scrounge around a junk planet for a replacement. Ultimately unsuccessful but in need of the part to win a fight, Coop goes down below. When he comes back up, Megas is back up and running and proceeds to kick butt. When Kiva asks how he fixed Megas, he replied, "When in doubt…duck it!" Kiva is uncharacteristically impressed, "Primitive…but amazing technology!"
In "A Service To The Community" the girls take a battered Mr. Collins that they beat up (long story) and try to think up a cover story to explain their teacher's Clothing Damage. Cornelia has a plan that involves Collins' lizard and its lunch.
Taranee: (while looking at said lizard) Too bad we can't just sprinkle him with crickets so he'll think Mr. Scales did it.
Cornelia: That's crazy.
Will: Do it!
In the episode "The Key", Will's plan to clear Vathek of helping Caleb escape boils down to framing a highly respected guard by slipping the key in the title into his armor and having Vathek fake being attacked...it works.
In "Homer Defined": Homer resort to "Eeny, meeny, miny, moe" method to save Springfield from a nuclear meltdown.
In "Lemon of Troy", Bart is trapped at the Shelbyville Zoo where he must escape or face the Shelbyville boys chasing him and tigers. Because he left during the lesson on Roman numerals, he can't find the correct door (number 7) because they're labeled in Roman numerals. He resorts to the Rocky film series, which had the numbers, and he's successful.
Many variants on this are attributed to Niels Bohr, notably to Wolfgang Pauli, on Pauli's nonlinear field theory: "We are all agreed that your theory is crazy. The question that divides us is whether it is crazy enough to have a chance of being correct." Reputedly, when Lee Smolin was running around proposing that black holes give birth to new universes, Murray Gell-Mann said, "Smolin? Is he that young guy with all the crazy ideas? He may not be wrong."
Back when legalized racism was rampant in the USA, no shortage of people were trying to find ways of eradicating it. You wouldn't have thought that simply not taking the bus would make a difference. Martin Luther King and those who worked with him proved otherwise.
After The Great Video Game Crash of 1983, stores refused to sell video game consoles and people were wary of video games. So what did Nintendo do? They packed in the Robotic Operating Buddy (which was a piece of garbage that worked with two games) so they could tell stores it was a toy, and they made it a front-loader so it resembled a VCR more than a gaming console. Today, Nintendo is one of the richest companies in the world. And then they did it again. A console controlled by a motion-sensing remote, you say? And it's not even HD? Ridiculous! Ridiculous enough to sell 67 million units in three years. And before that was the Nintendo DS, an absurd handheld gaming console with a flip-case design and dual screens, the lower one being a touchscreen. Initially mocked by critics, it became one of Nintendo's best selling products. The fact that they were willing to try anything this out-of-the-box after the Epic Fail that was the Virtual Boy shows that Nintendo has balls of Nintendium.
When they released the Citroen 2CV in Africa, they included a manual for alternative solutions when parts weren't available, which included things like shoe-laces (because Africa is mostly wilderness, having to resort to a bush repair is a very real possibility).
Politicians, scientists, and relief workers have been trying for nearly a hundred years to bring Africa out of the third world. One young boy, WilliamKamkwamba, decides to introduce the first ever steady electric power supply to his famine-devasted cholera-torn village. And he did it with a box of scraps!!!. The villagers called him "misala", meaning crazy, right up until the first light bulb lit up in his hands. Okay, he didn't do it in a cave, but he's still a bigger badass than Tony Stark 'cause he did it for real.
Wait, are you going to play your amp loud, resulting in distortion and then make the guitar loudest in the mix? When Eric Clapton did just that back in the Blues Breakers in 1966, he ended up inventing modern rock guitar as we know it.
Similarly, Jimi Hendrix stood with his guitar facing the speakers, becoming the first guitarist to use feedback deliberately in his music.
Alexander the Great's Siege of Tyre. The city was impregnable from land and sea. It was a goddamn island. So what did Alex do? Turned it into a peninsula. You can just hear the Tyrian general's Flat "What." as he saw it going on. The Tyrians reacted quickly to the situation and managed to hold off Alexander for a while by employing their sea advantage to hold up Alexander's initial attempt at a causeway. Only when Alexander tried again, this time with ships helping in the work, were the Tyrians defeated.
The Romans later did something like this during the siege of Masada. The fortress of Masada lay on top of a mountain and could be accessed only from a narrow road, meaning it couldn't be conquered by force, only by trickery (how the Jewish rebels had conquered it in the first place: they entered with a supply caravan), and trickeries couldn't be attempted in that situation. The Romans built a mountain-sized siege ramp to reach the fortress in force and with their siege engines, at which point the defenders killed themselves before the Romans could breach the walls.
Generals throughout history could occasionally get away with pulling off ostensibly insane stunts by exploiting this trope, usually involving an attack so unlikely (say, through a seemingly insurmountable desert, swamp or mountain range), the enemy is caught completely off guard (think the Blitzkrieg in the Ardennes Forest). If it's crazy enough, the enemy will never see it coming, and it just might work.
George Washington's desperate attack at Trenton during The American Revolutionshould have been a suicide mission. The weather was awful, and his army was small, undisciplined, had lost every recent battle it had fought, and needed to launch a coordinated attack across an ice-choked river at night. And do it all on the sly. Of course, the unwitting Hessians knew all this too, and thought that because of all this, Christmas of 1776 would be a fine time to let their guard down. It wasn't.
In the Eastern Theater of the The American Civil War, the Confederates put this trope to work early and often. The Union always had more men, so the only way for the Confederates to win battles was to innovate- often to the point of weirdness. It sometimes meant luring the Union generals into making fruitless attacks, and sometimes meant making their own unorthodox attacks at vulnerable spots. Robert E. Lee was a fan of the trope, and Thomas Jackson was the master gamesman of it. Ultimately, the trope was subverted. Jackson, the best practicioner of it, met an untimely death, hurting the Confederate's ability to deliver these types of battle plans. Meanwhile, Union generals slowly learned to simply expect the unexpected from the Confederates, and to retain the initiative in spite of Confederate tricks.
In WW2, like the French, the Belgians figured that an attack from the Germans was coming sooner or later, and they built a fortress to cover the most likely avenues of approach. The Germans responded by coming at it from what at the time must have seemed like the most unlikely avenue — the top.
Zhuge "Sleeping Dragon" Liang was a Chinese general famous for his masterful battle strategies and deceit. Once during the War of the Three Kingdoms, he was trapped in a town with only a handful of soldiers and an opposing army of a hundred thousand men approaching fast. He immediately sat himself atop the city walls with the gates wide open, calmly playing a lute. The leader of the enemy army, Sima Yi, was quite familiar with Zhuge's ingenuity and, thinking this was all a big setup for a deadly ambush, immediately retreated.
The fate of Apollo 13. So your Cool Ship has an explosion literally halfway to the moon. Here's the plan: 1) Use a machine designed strictly for landing and taking off as a lifeboat, even though it will have to support three people for four days when it was designed to support only two people for only two days; 2) Shut down all electricity, subjecting your crew to near-freezing temperatures (not to mention the havoc the frost is sure to wreak with the electronics when you have to turn them back on); 3) Kitbash a working carbon dioxide filter out of whatever you have lying around because the ones in the lifeboat can't handle the workload; 4) Carry out course corrections with an engine unsuited for such fine maneuvering, using such high tech navigational methods as "placing your thumb over the Earth and lining it up with your window frame"; and 5) Literally invent a new procedure to restart all your electronics so as to not blow every fuse in the craft, thus stranding yourself in space. The Subversion of this is, in the hands of ordinary people, yes, it would be Crazy Enough to Work. In the hands of NASA's highly trained corps of Steely Eyed Missile Men, it came off as almost...commonplace. The reality is somewhere in between; they weren't Crazy-Prepared for this type of situation, but they were trained enough not to panic even when Murphy's Law struck (note the tone of the now-famous line, "Houston, we have a problem."—concerned but not freaked out), trained enough to coordinate with mission control, work out a solution, and get home alive! Apollo 13 was a technological disaster but a human triumph.
That may or may not be the point of the Steely Eyed Missile Men; create unusual and ingenious solutions to unexpected problems under tight deadlines. Besides which, while the vague concept may be "just crazy enough to work", there's a helluva lot of effort put into making sure that everything is within the bounds of reality.
It was said later that if they had written the Apollo 13 situation up as a training simulation, it would have been rejected as unsolvable. That realization caused an official change of NASA training policy from "anything that's possible to solve" to "anything whatsoever".
Hannibal's conquest of Italy in 218 BC. The Romans never expected anyone to be crazy enough to march over the Alps, and certainly not for it to work. He did lose half of his army and most of his war elephants doing it, but he had Rome on the run for nearly 15 years.
In the end, the Romans won by outcrazying Hannibal. Invade Africa and attack Carthage directly (either getting Hannibal's leaders to surrender or forcing Hannibal to return home to defend them)? Costly, but doable. Invade Africa with only infantry and raise cavalry among Carthage's allies? A bit crazy, but Carthage's allies were more favorable to Rome and with a few legions in support they could finally rebel. Invade Africa with an infantry army composed of fresh recruits and the survivors of Hannibal's greatest victory? Crazy. Yet, Scipio destroyed Carthage's home troops and forced an armistice before a frantic Hannibal could return, and when Carthage broke the armistice and sent him Hannibal he defeated him too in spite of being outnumbered.
Notably, when Hannibal's army had just annihilated their best legions and was actually at the gates of Rome, leaving only a skeleton crew to defend the city itself, they sent an expeditionary force off to reinforce one of their overseas colonies. (Probably done solely to psych Hannibal out, but even so...)\\\ This was done because the Romans knew Hannibal's one weakness: he lacked the numbers to sustain either a siege or an attrition campaign. Hannibal could deal with the attrition campaign by outrunning the Romans, but he could never conquer a Roman stronghold (as shown by the strongholds of Placentia and Cremona, placed in Hannibal-friendly territory. The first resisted to the Gauls' siege for years, and the second resisted the entire war), much less Rome itself and the Roman-friendly populations around her. In the above mentioned situation the Romans didn't just send an expeditionary force to reinforce their overseas colonies (cutting off Hannibal's possible reinforcements in the process) precisely because they knew this, but auctioned the land he was camping on to drive the point home (the land was sold at the price of free land).
Taking a page from the Steely Eyed Missile Men, a number of folks in commercial aviation likewise summon crazy calm resolve to combat problems that arise. A most recent example, something, probably geese, gets caught in the engines of your loaded Airbus and blows them out. You can't circle back to the airport you left and you won't make the closest alternative. What do you do? Why, you just land the thing in the Hudson River. Captain Chesley Sullenberger and the crew ofUS Airways Flight 1549 did it.
Operation Desert Storm. US tanks drove through featureless, utterly unnavigable desert relying on barely proven GPS to catch the Republican Guard by surprise. (But unfortunately we went slow enough to ensure we were detected before we could actually use that surprise.)
In WW2, the British were seriously thinking about making aircraft carriers out of ICE. The idea was that they would mix sawdust with the ice (see Pykrete in the Other Wiki), which would hold off the ships from melting long enough, and be strong enough to double as armor. The main reason they were going forward with it was because it would require far less steel, which the blockaded Britian had very little of. However, it was subverted when they figured out it would take more steel to make refrigeration units needed to construct them than it would take to an aircraft carrier. Ultimately averted before any serious work began. By this time America with its unfettered industrial might was chipping in, and improved Allied air power was steadily one-upping the Wolfpacks. The situation no longer required such desperation.
Mythbusters decided to recreate this. They ended up substituting newspapers for sawdust, which on the small scale was much stronger than the sawdust. It worked better then they hoped and they were able to stay afloat for almost an hour. Adam Savage proclaimed the myth "Plausible, but ludicrous" as it wouldn't have been practical to do.
Murphy's law of war states: "If it's stupid but it works, it isn't stupid."
Napoleon's standard modus operandi was this, earning him a lot of apparently impossible victories (and half of his four decisive defeats when his foes were smart enough to realize what was going on). Some examples:
He's facing a well-equipped Royalist insurrection in Paris with an outnumbered army. To counter this, he fired cannons loaded with grapeshot (essentially transforming them into giant shotguns), causing the Royalist attack to lose any semblance of cohesion due to surprise and the losses incurred (a cavalry charge finished the job, causing the insurrection to dissolve). Grapeshot was not the crazy part (in fact, it was a standard load for cannons of the era), but using them in urban warfare was.
The Egyptian Campaign started with Napoleon running Nelson's blockade by having his fleet set sail during a storm (he knew the harbour better than Nelson, and knew that the only refuge for the blockade ships would have prevented them from noticing him slipping away). Napoleon's army was starved, demoralized and fighting against the strongest cavalry in the world. The square formation solved that, as did pointing out that the members of said cavalry went to battle wearing all of their jewels (the Battle of the Pyramids was such a Curb-Stomp Battle that the name of his foes, the Mamelukes, is now synonymous with 'idiots' in Italy). Then, Nelson destroyed his fleet, preventing him from receiving reinforcements or returning home in case things went bad. No problem, he would just return to France by conquering the entire Ottoman Empire, using locally-raised troops to replenish losses. The latter was one of his decisive defeats because British admiral Sidney Smith, who Nelson had left to keep an eye on the situation, realized what he was planning and reinforced/resupplied the fortress of Acre enough that it repelled Napoleon's siege (Napoleon would later be forced to abandon his army to return to France with a single ship).
The Second Italian Campaign started with another, with the Austrians blocking the way to Italy near Nice and him pulling a Hannibal and entering Italy over the Alps (something supposed to be impossible with cannons). Also, at Marengo, the Austrians had all but defeated him when Napoleon noticed he was about to receive reinforcements and had his troops launch an immediate counterattack right when the Austrians were preparing for the post-victory pursuit (though the timing of that counterattack owes much more to Generals Marmont and Kellermann Junior: together, with eighteen guns loaded with grapeshot fired at point-blank range (Marmont did learn his artillery tricks from Bonaparte) and something like two hundred heavy cavalrymen, they managed to hold off the attacking Austrian column (more than 5000 men) long enough for General Desaix to get the reinforcements into battle formation).
At Somosierra, Napoleon faced a highly fortified, windy mountainous ravine that was his only way towards Madrid. Instead of assaulting in full force, he sent his personal retainer unit of cavalry (several hundred at most). Taking the Spaniards completely by surprise, they scattered the dumbfounded defenders for long enough that the rest of the army could secure the positions. Notably, historians debate whether this was the plan, an awkward result of misunderstood order to scout ahead, or the cavalrymen wanting to show off.
The Russian campaign was supposed to be another: a sharp attack into Russia (something that was considered a suicidal attempt) to destroy the Russian army and force the Russians to join the alliance against Britain. Sadly for him, after the first few defeats, the Tzar placed Kutuzov into command, who completely outmatched him at a strategical level and ultimately kicked him out of Russia, aided by Scorched Earth tactics and General Winter.
Leipzig was the result of the Sixth Coalition pulling this on Napoleon: left with no generals capable of defeating Napoleon on the battlefield (with Kutuzov dead by an illness and the future Duke of Wellington being busy in Spain), the Allies fixed a few strategic objectives (including avoiding battles with forces commanded directly by Napoleon until they had mustered overwhelming force) and left to their armies to try and achieve them independently from each other. This not only gave them the overwhelming superiority they aimed for, but, when used on a tactical level at Leipzig, resulted in Napoleon rebuffing an Allied attack only for two other Allied armies showing up to prevent him from finishing the job on the first Allied army, ultimately forcing him to retreat with a crippled army and leaving almost half of it (including one of his marshalls) dead, wounded or captured. The gambit worked partly because the coalition had secured the help of Jean-Baptiste Bernadotte, a former buddy of Napoleon, who knew the tactics of Napoleon inside-out, and therefore Out-Gambitted his former boss.
Similar to Hannibal's example above, the Maginot Line during WW2 was very lightly defended near the border with Belgium, in part because it was believed nobody would ever be crazy enough to try to send tanks over the uneven and heavily forested Ardennes. Which, of course, was exactly what German forces did, bypassing the strongest part of the Line and sending the French forces into chaos trying to repel it.
Operation Chariot during World War II, also known as "The Greatest Raid Of All". The town of St. Nazaire in France had the only drydock capable of holding the massive Nazi battleship Tirpitz and thus the only port from which the battleship could attack Allied convoys supplying Britain with food. So, it was decided the drydock had to be destroyed. Unfortunately, a naval operation would be too dangerous and an air-raid too inaccurate. So, the British Commandos - the forerunners of the SAS - decided on a new plan: they would embark 265 of their best men onboard a flotilla of Motor Launches, tiny wooden ships with practically no armor and minimal armament. They would be accompanied by the ancient HMS Campbeltown, a WWI-era destroyer that began her career as the USS Buchanan, which would be packed with large amounts of high explosive and disguised as a German destroyer. The destroyer would ram the dock gate and then explode, taking the drydock out of commission. Meanwhile, the Commandos would run around breaking things before embarking on the Motor Launches for the return to Britain. It was Crazy enough to half-work - the gate was rammed, the Commandos destroyed things... and then found that most of their tickets home had been sunk. Most of the survivors surrendered after being surrounded and running out of ammunition, with 5 escaping overland to Spain. The Campbeltown, embedded in the dock gate, waited until the following day to explode, by which point it was crawling with enemy troops. The explosion totally wrecked the dock gate, and scattered bits of German so far and so high that human remains were still being found in 1968. The drydock was disabled for the rest of the war.
The Inchon landings in the Korean War. The difference between high tide and low tide at Inchon was very nearly 30 feet in the late summer — not really suitable for amphibious landings, since the ships launching landing craft would be likely to get stuck in the mud flats when the tide went out (and get stuck period six months later). So, the North Koreans weren't concerned with defending it. That was exactly why MacArthur expected it to work. Using Japanese tidal charts, the UN forces were able to accurately predict high tide and when ships could move in to release landing craft, then pull out before they got stuck in the mud flats. The result led to the first major turning point in the war.
Giuseppe Garibaldi once decided to conquer the Kingdom of Two Sicilies (the southern half of modern-day Italy) with a thousand underarmed people (one of them was a woman), facing off against one hundred thousands well-armed soldiers who knew he was coming. About six months later, Garibaldi had an army of fifty thousands, half of which defeated the last, underarmed and demoralized remnants of the army of the Two Sicilies. It succeeded for just one reason: the enemy knew the enemy force was coming but not that Garibaldi was in command. Two years earlier Italian unification patriot Carlo Pisacane had led a similar expedition that had ended with the lynching of the invaders at the hands of the citizens (it helped they had broke out a number of inmates from a prison, thus adding plausibility to the government's description of them as a mass of brigands and murderers), and the Two Sicilian commanders expected a repeat, assuming that the invaders actually ran the blockade (they did), and thus warned the people. The one difference was that Garibaldi was well known as a freedom fighter and had been smart enough to invade Sicily proper, that didn't like the government of Naples and was thus able to start an insurrection and cause mass desertions in the enemy army.
The Sardinian and later Italian militaries love this. A few examples:
Sardinia was scarce in cavalry, as both Sardinia proper and the mainland were mostly mountainous lands with little space for the horses. They raised the Bersaglieri, assault infantry noted for their good aim ("bersagliere" is Italian for "sharpshooter"), their wide-brimmed hat decorated with capercaille plumes (that shielded their eyes from the sun and helped aiming), and running all the time, and expected them to hold off cavalry charges with a square formation and then countercharge as they regrouped. They had the chance to try it only once, but when they did they routed a Russian Army.
During World War I, the Italians mounted torpedoes on commercial speedboats, called them MAS and used them as patrol ships and harbour raiders. The Austrian flagship was sunk by two of those speedboats.
The Maiale (Italian for "pig") was a long-ranged but slow-moving torpedo with a detachable warhead that is supposed to be steered in an enemy harbour by two frogmen, who then detach the warhead, place it on the hull of an enemy warship and then leave before they explode and sink the ship. In World War II, two British battleships were sunk in Alexandria's harbour during a failed raid (the main target were the carriers, who weren't in harbour), among similar raids performed by the Decima Flottiglia MAS
The effectiveness of these kind of raids was such that the Allies tried to copy them with mixed results, and when Italy switched sides they called in the members of the Decima remained with the King's government and had them train their special forces.