A light-hearted mix of RoboCop and Inspector Clouseau, Inspector Gadget was an animated crime-fighting police detective who traveled the world "solving" crimes.His namesake body was loaded with an assortment of non-lethal slapstick crime-fighting tools that he could activate by saying aloud "Go-Go Gadget..." and then naming the tool he wanted to use. Among the most prominent were his telescoping arms, spring loaded legs, inflatable trench coat and a hat that contained a helicopter propeller that allowed him to fly. Gadget also had a laser built into his finger, but never used it to actually blast any living thing.Actor Don Adams provided Inspector Gadget's voice, and much of the inspiration for the character was drawn from Adams' live-action portrayal of bumbling secret agent Maxwell Smart in Get Smart. Also carried over from the live-action show was the manner in which Gadget received his orders from his superiors. Chief Quimby would contact Gadget on a built-in telephone and arrange a meeting, giving Gadget his intelligence on a self-destructing sheet of paper. Later on in the series veteran voice actor Maurice LaMarche would take over the role of Gadget.Gadget's nemesis throughout the series were agents of the MAD organization: a global crime syndicate with operatives just about everywhere who specialized in the looting of national treasures and world financial markets. Swiss gold reserves, the Amsterdam diamond exchange and Egyptian artifacts were just some of the financial and cultural properties targeted by MAD at some point. It also gave excuses to send Gadget and company to exotic locales such as the Amazon River, the Andes Mountains or the African savannahs.By the second season, the action focused less on traveling the world and stayed localized to Gadget's Metropolis-esque home town of Metro City. These episodes featured MAD scientists (both literally and figuratively) inventing new technologies for MAD agents to commit mundane crimes with a sci-fi twist. A machine that hypnotized normal people into robbing banks, shrink-rays, plant-growing chemicals and a teleporter that sent users though normal phone lines were all featured.Pulling the strings of the MAD cabal was the nefarious Dr. Claw, a (mostly) never-seen Big Bad who ended each episode defeated, declaring he'd get Gadget the next time.Much of the actual detective work of the series was performed by Gadget's niece, Penny, and the family dog Brain, who was a master of disguise. The duo would solve the case behind the scenes using Penny's high-tech "computer book" (a laptop before such a thing was invented which could receive data seventeen years before wi-fi became a consumer technology) while Gadget's gadgets would send him careering about the landscape like Remington Steele on roller-skates. Penny would have many close scrapes and exciting adventures of her own. She would oftentimes get captured and either imprisoned or tied up, and require rescue, or manage to escape on her own.Penny and Brain never took credit for their work, leading others to regard Gadget as a brilliant detective, and several comical attempts on his life were made by MAD assassins. Gadget would invariably mistake these assassins for helpful allies and would always assume the disguised Brain was an enemy agent.Indeed, Penny's role in the cartoon's plot is so vital that the show actually works pretty well if you remove Gadget himself from it and focus only on Penny.Despite its many varied locales and plots, the show was Strictly Formula, using the above-mentioned plot elements in literally every single episode, albeit sometimes with creative variations. For example, sometimes Penny makes friends with other kids who help her out with her investigations. Gadget could also show more isolated moments of competence if the plot required it. In fact, if the show were any more formulaic, they would simply show the same episode over and over.A total of 86 episodes were produced by DiC Entertainment for syndication between 1983 and 1985. Gadget stayed in syndication well into the 1990s before being largely retired. Maurice LaMarche also made a Live-Action appearance as Gadget on The Super Mario Bros. Super Show.The titular detective made his big-screen debut in 1999, played by Matthew Broderick; a direct-to-video sequel starring French Stewart followed in 2003. The first film was Darker and Edgier and barely resembled the series; the second, while more faithful, was even more derided than the first. There was also a spin-off series called Gadget Boy & Heather which shares little in common with Inspector Gadget but bionic implants, and also a more faithful spin-off called Gadget And The Gadgetinis.A CGI Continuity Reboothas been announced to air on Teletoon in 2015.
Accidental Hero: Although Penny and Brain are typically the ones who actually realize what's going on and save the day, Gadget's screw-ups are often an enormous help to them. Of course, he intends to solve crime and stop the bad guys, but he only ever succeeds accidentally (with a handful of exceptions)
Accidental Misnaming: Gadget frequently refers to Corporal Capeman as "Capman". Capeman never seems to mind or bother to correct him.
Action-Hogging Opening: The opening shows Gadget being more competent than he is in the actual show. The same goes for Gadget Boy in his show's opening.
Adults Are Useless: Were it not for a 10-year-old girl and her pet dog, the world would have fallen to MAD years ago. However, when Gadget knows Penny is in danger, he becomes scarilycompetent.
All Men Are Perverts: Whenever there is an attractive female M.A.D. Agent, you can almost always count on Gadget falling for her.
All There in the Manual: Merchandise of the show released in the early 1990s, along with a Little Golden Book from 1984 (Inspector Gadget in Africa), revealed that MAD stands for Mean And Dirty.
Other pieces of merchandise say it stands for Malevolent Agency of Destruction.
This is the second time in cartoons that a criminal organization called itself "MAD." The first time was on 1966's Tom Of T.H.U.M.B., a segment of the ABC King Kong show. MAD in that case stood for Maladjusted, Anti-social and Darn mean.
This also is explained as where he got the toys in the Live Action Adaptation. Only with a billboard instead of a banana peel.
The recurring M.A.D. Agents we see in every episode have names, although they were only used on their design sheets and in the scripts of the episodes. The names of the M.A.D. Agents are: Fred (big man, crooked nose, flat head), Lenny (big guy, bulbous nose), Dick (skinny man), Slick (resembles Dick, but with white hair, a mustache, and a goatee), Pops (A bald, hunched-over man with a large chin), Bruce (muscular man with a large chin), Squirt (short man with scrunched-up face), and Jarvis (fat, balding man).
And Knowing Is Half the Battle: At the end of each episode, as per the standard at the time, Gadget, Penny and Brain would teach the kids a safety tip like "exercise is good for you" or "always wear a seatbelt". Where it gets weird is, it's always Gadget providing wise advice to Penny. This complete reversal of his usual stupidity is blatant enough to suggest he's actually been trolling her and Brain in the main show all this time. In the first season, it was typically related to the episode in some way ("Down on the Farm" had safety about farm animals and equipment, "Health Spa" had advice about exercise and good health, "Race to the Finish" had automobile safety, "Basic Training" had train safety, etc.) or would relate to something that happened in the episode.
Animation Bump: The TMS episodes animated by Shingo Araki's animation unit, including "The Curse of the Pharaoh," "The Coo-Coo Clock Caper," "The Bermuda Triangle," "Did You Myth Me?" and "Unhenged." In these episodes, the animation and designs are of a noticeably higher quality, with slightly rounded designs and more detailed facial features, and the movements are fuller and cartoonier. The Telecom animation directors such as Saburo Hashimoto, Nobuo Tomizawa and Toshihiko Masuda also contributed some high-quality animation as well.
Animesque: Due to TMS Entertainment (andafewotherJapanesestudios) working on this series, this is a given. Season 2 more so than season 1, due to DiC opening their own Japanese animation house by this time (though some of the aforementioned studios still did ink-and-paint/camera work).
Subverted in a few episodes when Gadget is the one who saves Brain. Notable examples include Photo Safari (when he saves himself, Penny and Brain from crashing after MAD agents sabotage their plane), MAD Trap (when he saves himself, Penny and Brain from being burned alive by a fire), The Bermuda Triangle (when he uses his copter to escape from an exploding ship and takes a disguised Brain with him), The Great Divide (when he saves himself and Brain from being crushed by a cave-in), Did You Myth Me and Tree Guesses (in both episodes, Gadget thinks the disguised Brain is an enemy agent and catches him before he'd fall to his death).
Berserk Button: Dr. Focus reacted badly to anyone who called him a Mad Scientist, or even when the term "M.A.D." is used. And then there was the fact that Dr. Claw would burst into fits of rage whenever he saw, or even simply had to mention Gadget.
Apparently finding out someone is messing with Penny is enough to make Gadget act competent.
Bigger Bad: In the episodes "Gadget Meets the Clan", "Gadget and Old Lace", and "Gadget and the Red Rose", we are introduced to Dr. Claw's mentor Les Renowned. He isn't really much of a threat, but considering he taught Dr. Claw everything he knows....
Busman's Holiday: Gadget frequently finds himself assigned to cases while technically off duty, even though one of his catchphrases is "I'm always on duty!"
Calling Your Attacks: Every time Gadget is going to use one of his gadgets, he says, "Go-Go Gadget Copter/Mallet/Phone/Scissors/Laser/Skates/Radar/Arms/Legs/Coat/Binoculars/Key/Whatever!"
Which leads to a funny situation in "Fang The Wonder Dog", where Gadget says "Go go Gadget Key!" and gets his flashlight instead. He then points his index finger (where the flashlight is coming from) at his face and nonchalantly says "I said 'Go go Gadget key!'"
Cartoon Bomb: Gadget ends up handcuffed to one of these in the opening.
One also appears in the commercial bumpersnote In the pilot (where he had the mustache), it was black, while in the series it was red., with the lead-out bumper showing that it had exploded.
Catch Phrase: "Wowsers!" "Go-go Gadget..." "Inspector Gadget is always on duty!" "Stop in the name of the law!" and "I'll get you next time, Gadget... Next time!"
"What's that, Chief? You're where?" as well as "why do I put up with him..."
While it's more a generic exclamation than a Catch Phrase, Penny's "OH NO!" is used so recurringly and with the same exact tone it may as well be one - she also tends to cry "Crumbs!" when something doesn't go well.
Chariot Race: Inspector Gadget helps his Roman ancestor Gadgetorum win a chariot race in the Time Travel arc of the series.
Cloudcuckoolander: Of course Gadget is one, but Mayor Markham from Inspector Gadget's Biggest Caper Ever is an even bigger Cloudcuckoolander. He is obsessed with Martians, confuses the Wright Brothers with Frank Lloyd Wright, and frequently failed to get the point when Chief Quimby tried to explain that Dr. Claw broke out of prison.
Comic Book Adaptation: Back in 2011, one made by Viper Comics surfaced, and is closely based on the original TV Show.
Conservation of Competence: For the bad guys, many of the henchmen are incompetent, and for the good guys, Gadget, who is usually only competent when Penny and Brain are captured.
Continuity Nod: In the episode "The Amazon", we are introduced to Professor Von Slickstein, the scientist that gave Gadget his gadgets. He later returns in the episodes "Tyrannosaurus Gadget", "Gadget's Roma", and "Gadget's Clean Sweep" to help Inspector Gadget, Penny, and Brain go back in time to prevent M.A.D. agent Thelma Botkin from killing Gadget's ancestors, although in those episodes Slickstein has a different voice and his name is pronounced differently (Slick-STEEN instead of Slick-STINE).
In "Funny Money", Gadget mentions wanting to cook his specialty using blueberries and cabbage, which he previously tried to do in "Gone Went The Wind".
Brain's persisting fear of ghosts from "The Haunted Castle" returns in the Season 2 episode "Ghost Catchers." Likewise Penny, who thoroughly got over her fear in the former episode, remains totally adamant that ghosts do not exist, the same as her Uncle.
Conveyor Belt-O-Doom: Seen in "Quimby Exchange," "A Star is Lost," "Clear Case," Dutch Treat," "All That Glitters."
Cool Car: Gadget's minivan transforms into a police interceptor car, and also had built-in gadgets. In fact, the interceptor mode is heavily based on the French-built Matra Murena.
And the MAD-mobile, which could transform into a jet or a submersible. And packed weaponry to boot.
Corrupt Corporate Executive: Dr. Claw crept into this territory in a few episodes. MAD would set up perfectly legitimate businesses like dairies or hotels, and then the Evil Plan would be to wipe out the competition by some underhanded means.
Covered in Gunge: Happens to Gadget, almost as often as Penny getting Bound and Gagged. Milk, cheese, Dutch chocolate, mud, crude oil; you name it, he's probably been covered in it at some point.
Cut Lex Luthor a Check: Dr. Claw invents numerous super advanced technologies to... rob banks and steal valuable objects.
For the series itself, while there's no clear trend of it, certain episodes are notably darker than the norm. For example, "The Boat" is much more explicit than usual about Claw's occasional mass murders as a group of witnesses are shown about to be drowned by M.A.D. agents. It also unapologetically shows Claw drowning Gadget slowly while forcing little Penny to watch. Other, less blatant examples include episodes "Dutch Treat" and "Launch Time".
Death Ray: In the episodes "Unhenged" and "The Ruby".
Death Trap: Countless types used by MAD in every episode, although no one dies from them, and they often backfire on MAD agents.
Brain can also be a rather cheerful and enthusiastic assistant when not suffering under Gadget's aforementioned incompetence, or a Nervous Wreck driven to wit's end by his abuse. It's worth noting these two character examples were sometimes actually reversed in a few early episodes, with Gadget being semi competent and occasionally annoyed by Brain's bumbling.
Disproportionate Retribution: In episode 1-6 "Health Spa", Gadget looks in his rearview mirror and sees someone (Brain) on a scooter following him. He automatically assumes it is a MAD agent and fires missiles and uses an oil slick against despite the fact that the only thing this person is "guilty" of is being behind him on the road.
In "The Incredible Shrinking Gadget", Chief Quimby, after being accidentally shrunk, threatens to fire Gadget if he doesn't return him to normal size.
Doomsday Device: The Crystal Weapon, the earthquake machine, the weapon in "The Japanese Connection", etc.
Dub Name Change: Penny and Brain are named "Sophie" and "Finot" in the French version of the show.
For some reason, the characters bear their French names in the German version too.
Probably because the French dub was the basis for some other European dubs. A first Italian dub in the 1980s was based on it, while a newer dub in 1993 was based on the original version and restored the names with the exception of Brain, who was renamed "Bravo".
In the episode "In Seine", Gadget is given a belt for his trenchcoat with a bomb built into it. Brain pushes Gadget into the water, managing to remove his belt and dunk it into the water.
Another episode, "Art Heist", has Gadget get a glowing ball which is activated by Dr. Claw and turns incredibly hot. Brain gets it away from him yet again and throws the hot ball into a fountain. It explodes, sending up a big column of water.
A double subversion in "Amusement Park", where Gadget received a panda bear as a reward for hitting two of three ducks. This bear contains a bomb set to blow up in 30 minutes, which Brian attempts to throw into the amusement park pool (only to be caught by Gadget's long arm). When Chief Quimby shows up, he stumbles and accidentally drops the bear into the pool.
Early-Installment Weirdness: Gadget, while still bumbling, was far more competent in the pilot, and used his gadgets with clever, deadly accuracy as well. This interpretation reappeared in a handful of early episodes (eg. "Haunted Castle") but ultimately faded in favor of his Inspector Oblivious persona.
Also, he had a mustache. This was dropped because it made him a little too much like Inspector Clouseau.
Another oddity from the pilot was that Gadget's gadgets made beeping sounds whenever they activated.
When Gadget is electrocuted during one of the end of episode safety tips, he even gets out a, "Would you believe..."
And Dr. Claw is, of course, an expy of James Bond's faceless, cat-stroking arch-nemesis, Ernst Stavro Blofeld.
On the DVD containing the first 32 episodes, Andy Heyward (character creator) commented that Gadget and Brain are Inverted Expies of earlier characters called Blue Falcon and Dynomutt, only this time, the human was the bumbling mechanical android, while the dog was hyper-competent.
Expressive Hair: Gadget's hair droops when he's sad, disappointed, or surprised. For example, when Gadget goes through in-universe Mood Whiplash in the episode M.A.D. Trap.
The Faceless: Dr. Claw in the cartoon. Bodiless, too. The only parts of him that were ever shown were his forearms.
A Dr. Claw action figure was released during the 1990's that showed his face, as did the Super NES game released by Hudson Soft.
In one episode, set in Japan, we see Claw's shadow, but it's a generic, blob like shape that gives no indication of what he looks like. However, another shot of the same shadow later on suggests that he seems to be wearing a hood/cloak of some kind.
Fanboy: Corporal Capeman is this to Gadget. He even looks (and acts) the part, with the dorky demeanor, extreme clutziness and geek glaases.
Fearless Infant: Gadget was shown to be one in a flashback of the final episode, where he is seen as a baby witnessing crime boss Spuds Malone gun down people with his potato gun the Red Rose and being completely unfazed by the chaos.
Film Felons: MAD once used a fake film production as an excuse to spy on a military base. (Hey, they were filming!)
The Fool: Gadget often obliviously keeps himself out of danger, and in some cases, even outright saves the day, due to well timed slapstick bumbling.
Forgotten Superweapon: Oh, once an episode a loyal viewer can think of a gadget that Gadget could have used which would have saved him some time. The Gadget laser is one incredibly underused gadget, but it is a kid's show.
In one episode, he even tries to deliver Gadget's assignment in a helicopter, landing on a ledge to keep Gadget away from him. Needless to say, this backfires on him.
In "M.A.D. Trap" Brain tries to get Gadget to follow him by disgusing as a crook, knowing he will once again mistake him for the real deal and give chase. Ironically it takes a while for Gadget to notice.
The "Movie Set" episode, in particular anything involving Lana Lamour.
Actually happens quite a bit. In "Race to the Finish", Inspector Gadget gets drunk when a M.A.D. agent gives him a funny drink. In "Busy Signal", he comes across a woman in a bathrobe, who calls him a "pervert".
Actually, he gets called a pervert several times throughout the series.
In "Race to the Finish", Gadget has his pen come out his middle finger, and flips some people off in the process. The people even react as if Gadget intended to flip them the bird!
And his flashlight seems to be in that same finger in episodes such as "Haunted Castle". Though it may seem like it was done on purpose, it sometimes alternates to his index finger as well.
In one episode Gadget is counting things he knows about a criminal by ticking them off on his fingers. He starts with his middle finger, with the back of his hand facing the audience and taking up a fair portion of the screen.
The animated DTV movies have some interesting moments...
Inspector Gadget's Last Case is chock full of it. Gadget mentions to his talking Gadgetmobile that one of the benefits of retirement is that he could be surrounded by "hot convertibles with their tops down". In addition, the conflict between them has interestingsubtext, to say the least.
When Mayor Markham askes where his brain was in Inspector Gadget's Biggest Caper Ever, Chief Quimby answers with "I don't know, Neptune, or Uranus, maybe?" Given what Uranus sounds like, it seems Quimby was implicitly telling the mayor he had his head up his ass. Also, Penny gets the Giant Flying Lizard's attention by calling it "guano-face".
At least one episode involved Brain - disguised as a hula dancer - slowly undressing parts of his disguise and leaving it for Gadget to follow.
Especially notable because Gadget says "This is getting serious" when he sees the discarded coconut bra.
Only for the original series however, as this served as a lead up to Gadget And The Gadgetinis. Inspector Gadget's Biggest Caper Ever seems to take place last chronologically so far (despite a few continuity issues).
G-Rated Drug: In "Race to the Finish" at a pitstop a MAD agent gives Gadget a mysterious liquid that makes him drunk.
Hammerspace: The only explanation for how all those gadgets fit into Gadget's body, plus where Brain must keep all of his costumes.
Heel-Face Turn: Nervous Nick Defecto in "The Quimby Exchange", The Grappler in "Gadget Meets the Grappler".
Highly Conspicuous Uniform: Agents of M.A.D. often wear jumpsuits with the M.A.D. logo emblazoned on the chest in public. Despite this, Gadget never realizes that they are his enemies.
Hoist by His Own Petard: One episode where Doctor Claw entered the MAD Mobile in a race against Gadget and the Gadgetmobile had him successfully drug Gadget and win the race, only to get himself disqualified after he switched to jet mode and left the track.
Another episode involved the device that a MAD agent had given Gadget that caused his gadgets to go haywire every hour caused the destruction of the agent's own clock factory when Gadget's gadgets went crazy while he was in one of the agent's deathtraps.
Hollywood Density: Averted; Penny realizes that a gold brick is a fake because she can lift it.
Hyperspace Arsenal: Apparently, many of Gadget's gadgets, such as the Mallet, the Sail, the Copter, the Phone and many more are actually all kept in his hat. And then there's Brain, who seemingly carries around an array of disguises despite being a dog with no visible means of holding his outfits.
Hyper Competent Sidekick: Penny, who really doesn't care where the credit for the victories go, as long as her Uncle Gadget (and the world) is safe.
Brain is this for Penny as well, as the dog always manages to get the job done, no matter how difficult things could be.
"It" Is Dehumanizing: While Gadget will refer to himself as a man, he doesn't raise any sort of fuss in an episode where MAD agents call him 'it' several times.
It Was a Dark and Stormy Night: Dr. Claw's hideout is usually in a spooky old castle with a thunderstorm brewing outside it, even when the weather is nice in Metro City!
Karma Houdini: Dr. Claw always gets away no matter what, although it is sometimes averted(e.g., in "Gone Went The Wind", he gets caught in the explosion of the Sneezooka while making his getaway and is trapped at the bottom of the arctic waters at the end of the episode). There were also some episodes in the first season where the M.A.D. Agent of The Week was not seen or mentioned as being arrested by the end of the episode, such as The Rat in "M.A.D. Trap". Things got worse in the second season, which mainly consisted of three-episode story arcs with the same M.A.D. Agents, each one avoiding capture in the end (The Great Wambini, Dr./Professor Dummkopf, Dr. Spectrum, Dr. Null and Dr. Void, Thelma Botkin). Only two agents of the week in the second season were ever arrested: The Ninja in "The Capeman Cometh" and Dr. Noodleman in "Gadget's Gadgets".
Kindhearted Simpleton: Gadget means well in his antics and is trying to save the day, he's just completely inept about it.
Knight of Cerebus: Dr. Spectrum, recurring M.A.D. agent in the season two episodes "Ghost Catchers", "Busy Signal", and "Bad Dreams are Made of This". His episodes still have the signature slapstick and humor, but Spectrum himself has few humorous qualities and is the most seriously played of Dr. Claw's minions.
(after Gadget figures out Claw is behind the recent crime wave) Penny: "Um... Uncle Gadget, Claw's been behind every crime this city has ever had."
Leaning on the Fourth Wall: In one episode gadget is shoveling his driveway when he says: "I haven't seen this much snow since that episode in the arctic."
Large Ham: Dr. Claw, saying "GAAAAAADGET!!!" and "I'll get you next time, Gadget... NEXT TIME!"
Laughably Evil: A good number of the M.A.D. Agents, and sometimes Dr. Claw himself.
Laugh with Me: An inversion; Dr. Claw frequently punishes his cat for laughing with him.
Lawful Stupid: Gadget to a 'T', so much that he thinks childish students sticking out their tongues are suspicious, and that the high-school chemistry teacher is training students in making explosives. He could be stopped in his tracks if MAD agents did something as simple as putting up a red traffic light in the middle of nowhere. Capeman as usual was even worse, once calling a tow truck on the Gadgetmobile for being illegally parked while on a case. Naturally, the truck driver is a MAD assassin who puts the two into a Death Trap.
Leitmotif: Examples include the main theme (Gadget's theme), Penny's theme, Brain's theme, Claw's theme, the Cuckoo Clock theme, the chase theme, and several Recurring Riffs not associated with a particular character or event. Some of the more commonly used background music shared something in common with some background music from She-ra, Princess of Power. Not surprising since both shows had the same composers, Haim Saban and Shuki Levy. Several pastiches of real songs were used, in fact the main theme is based on In The Hall of the Mountain King.
"Petite Sophie" from the French soundtrack is Penny's theme with lyrics added.
Logo Joke: The original closing logo had Gadget stumbling into the shot on his Gadgetskates and using his mallet to dot the "i" in "DiC".
Lost Superweapon: In the "Emerald Duck" episode, the Wave Motion Gun-like Crystal Weapon, which can level mountains and, if left uninhibited, destroy the entire planet. It even turns on Dr Claw himself.
Man in a Kilt: Brain wears a kilt most of the Loch Ness episode, and you can see up the kilt many, many times. He's not wearing anything under it, but then he is a dog.
Master of Disguise: In the "Infiltration" episode, M.A.D.'s undercover specialist Presto Change-O. Also, depending on interpretation, Brain. While his disguises appear quite unconvincing to the audience, they fool literally everyone in the show. (Not just Gadget, who can admittedly be fairly oblivious to reality at times.) And that holds true whether he's impersonating a lion, a hula girl or a military police officer.
Penny's French name, 'Sophie', is a French variant of the Greek 'Sophia', which literaly means wisdom
Mooks: MAD agents wore suits with the word "MAD" on them!
Monster Mash: The episode "Haunted Castle" featured a trio of M.A.D. agents dressed as a vampire, Frankenstein's monster, and a werewolf.
Monster of the Week: Dr. Claw had a new special MAD agent almost every week, who would try to carry out their assignment, get arrested, and never be seen again.
Averted in Season 2 somewhat, in which most of the new M.A.D. agents appear in three episode story arcs and are never arrested. Examples are The Great Wambini and the Lesser Wambini, Dr. Dummkopf, Dr. Spectrum, the Creepy Twins Null and Void who cause mischief (IN SPACE!), and Thelma Botkin.
Granted being Gadget, they were only useful to the plot in a handful of instances.
Nice Hat: Gadget's hat contained a personal helicopter, police lights, etc. The hat was also partially sentient, as it could be seen using a robotic hand to stop and warn Gadget about impeding danger or a bad decision, all by itself.
No OSHA Compliance: The record factory from "A Star Is Lost". The conveyor belt that carries Gadget, Penny, and Rick Rocker is an especially notable example; there's absolutely no reason for the conveyor to begin at any point before the actual record press (To say nothing of the size of the press itself). Ditto for the ice factory in "Quimby Exchange"
To the point that in one episode, "Volcano Island", Gadget survives a friggin' volcano eruption. To picture this correctly: he was standing on top of the volcano, leaning on the edge of its mouth and gazing inside it.
A Nuclear Error: One episode, "Down on the Farm", features an attempt to fire an American nuclear missile at a city. See the entry for the reason why this is nonsense (said episode has said missile stationed in a farm silo as sort of a parody).
Obfuscating Stupidity: Brain's French name of "finaud" and the lyrics of the French version of his theme song both allude to his hiding his competence behind his harmless outward appearance.
Off Model: The first season split most of the animation between TMS and Wang Film Productions (some episodes were animated by AIC, Toei Animationnote uncredited, Oh Production and Ajia-Do). The second season's animation was largely done by DiC themselves with help from some minor Japanese studios that were never heard from again (except one). This trope, of course, comes to play because of this.
One interesting twist to the Self-Destructing message was in M.A.D. Trap where Inspector Gadget gives Quimby a note asking "Have you got any assignments for me?" Followed by the "This Message will Self-Destruct" warning. Quimby freaks out, but loses it when nearby pigeons peck at it. Quimby tries to shoe em away, only to get caught in the explosion.
Papa Wolf: When he knows Penny is in danger, Gadget becomes virtually unrecognizable (and unstoppable) as he becomes the superhero he is supposed to be.
This is pretty much the entire plot of the SNES game, in which Penny gets kidnapped and you have to rescue her.
Paper-Thin Disguise: Both Brain and the MAD agents use these regularly. Penny can generally see through them, but Gadget NEVER can. (This is why he always thinks Brain is a MAD agent, and never realizes he's his own dog!)
Gadget himself did this once. His disguise consisted of a fake mustache and glasses. Everyone saw through it. EVERYONE.
Chief Quimby would sometimes wear one when giving the secret message to Gadget.
Penny wore one in a wild west themed episode, and Gadget didn't recognize her either.
Plot-Driven Breakdown: All the time. At least once an episode the wrong gadget will activate, a gadget will outright not work when he needs it, or do something else.
In fact, it was a surprise whenever a gadget worked correctly.
The malfunction often involved, instead of whatever gadget was requested, a big hammer coming out of Gadget's head and bonking either him or some other object/person in the area (which occasionally actually turned out well).
Police Are Useless: Gadget, despite being hailed as Metro City's best detective, has never come close to actually solving any of his cases, and on the rare occasions where other police or military personnel get involved, they aren't much better.
Power Crystal: The ruby in "The Ruby", and the weather control crystal in "Weather in Tibet".
Psychopathic Manchild: The Grappler from "Gadget Meets the Grappler" is a Type A. He is a childlike brute who obeys orders in exchange for candy (often donuts). His sweet tooth was used by Penny to stall him from his mission of destroying Gadget and eventually get him to betray M.A.D.
Smart Ball: Gadget, who could show competence whenever it was necessary to advance the plot. Several of MAD's attempts to derail the train in Basic Training were thwarted by Gadget himself, while in The Ruby Gadget defeated the tigers Dr. Claw sent after him on his own.
In one episode, "M.A.D. Trap", Dr. Claw's so fed up with Gadget ruining his plans that he enlists one (or more, not sure) agent with specifically killing him. Gadget is lured into an abandoned warehouse full of death traps; Penny is aware of the death order issued by Claw but both her and Brain are unable to directly intervene to save Gadget from the traps. The inspector though picks up the Smart Ball and counters each trap or attempt at killing him, managing to escaping the warehouse in the end, all traps deactivated or destroyed. And he was perfectly aware of the situation, all along!
During the pilot episode, Gadget had the Smart Ball glued to his hands all the time, at the point he's completely unrecognizable.
Also in the Grand Finale, the made for TV movie "Inspector Gadget's Last Case". He's still somewhat bumbling, but significantly less so than usual. Penny and Brain get less screentime.
Snooping Little Kid: Exactly what Penny is, as she is frequently wandering around in the enemy's current base of operations in her attempts to stop them. Sometimes she joins forces with another Snooping Little Kid and they work together.
Spanner in the Works: Despite being a complete and total nimrod, Gadget often helps Penny and Brain save the day through his clueless bumbling.
A literal case of this is when he becomes trapped inside a giant robot Loch Ness monster. He finds the inner workings, and while attempting to make some 'minor adjustments', he gets caught inside and makes the robot to go haywire.
Spot the Imposter: Dr. Claw hired a Master of Disguise named Presto Change-O in the episode "The Infiltration" to infiltrate a police conference disguised as Gadget to eavesdrop as a spy. When the real Gadget confronts Presto Change-O in the conference room, no one can tell who the real Gadget is until our hero stands next to Chief Quimby. Gadget's mallet activates by itself and bonks Chief Quimby on the head, and the Chief immediately orders that the other guy be arrested, since the one next to him is obviously the real Gadget.
Stage Magician: The Great Wambini and his bumbling assistant The Lesser Wambini from the episodes "Magic Gadget", "Wambini's Seance", and "Wambini Predicts".
Stealth Pun: In one episode, Gadget meets an unnamed MAD agent who works as a peat digger. Gadget obliviously just calls him "Pete" for the rest of the episode.
Stock Footage: The first season often tended to recycle the same animation of the Gadget Van changing into the Gadgetmobile (also seen in the intro) and the same animation of Gadget reading his assignment (both clips were animated by the Shingo Araki unit at TMS.)
The episodes animated by Wang Film Productions also had their own set of stock footage, in one case even using the aforementioned clip of the Gadgetmobile in "Smeldorado."
Strange Salute: Dr. Claw's henchmen essentially punch themselves in the temple to salute their superiors. It's accompanied by a hollow knocking sound effect, and it looks like it hurts(on more than one occasion, an agent salutes at the end of a conversation and knocks themselves out). More than likely, Dr. Claw made it up so his minions would injure themselves for his amusement. Though his agents repeatedly concussing themselves probably isn't doing their intelligence any favors.
Strictly Formula: Albeit played with in several episodes. Sometimes Gadget shows competence, sometimes Penny is kidnapped and doesn't contribute at all, sometimes Brain openly accompanies Gadget, sometimes Penny has another Snooping Little Kid helping her, sometimes Dr. Claw intervenes directly in the action, and so on.
The Gadgetmobile is dropped through the air by a plane. Gadget: Go-Go Gadget Plane! Gadget emerges from the car in helicopter mode. Gadget: Not Gadget Copter, Gadget Plane! Gadget PLANE! The copter goes back into his hat, and the mechanical hand throws out a paper airplane. Gadget: Not...exactly what I meant.
To be fair, at the end of one episode, he was shown as alarmingly competent. Not only does he show awareness of what's happening to him, but he also manages to save Penny AND Brain, PLUS his gadgets were working perfectly. If he showed this level of competence all the time, he'd be a force to be reckoned with.
Totem Pole Trench: In the episode "Weather in Tibet", Penny and a friend of hers do this to sneak past some guards.
Tricked-Out Shoes: His hat deserves all the credit it gets, but Gadget's shoes shouldn't be overlooked. They can turn into everything from roller skates to skis to ice skates to magnets on command.
Unnecessary Roughness: In Race to the Finish Dr. Claw enters a car race for the prize money. He blatantly forces the other cars off the track in front of everyone, but isn't actually disqualified until he activates the Madmobile's jet mode and flies to the finish.
Bounces around with Gadget himself. Sometimes no one seems to notice Gadgets obviously strange appendages, sometimes onlookers stare with a confused expression. However no one freaks out or asks questions.
When Penny appears to her uncle at the end of an episode, Gadget says "Penny?" but never reprimands her for not staying home - even if he's on the other side of the world from Metro City.
Vanity Plate: All first season episodes ended with a customized "D.i.C." logo where Gadget clumsily dots the "i" with his Gadget-malletnote This is similar to another logo used for The Littles, which premiered the same year, in which Dinky dots the "i" with a button.
Vengeful Vending Machine: The show once had a villainous Master of Disguise called Presto Change-O. At one point during his episode, Gadget thinks he's found the foe disguised as a vending machine he was running around disguised as Gadget. Naturally, this goes about as well as expected, with Gadget getting his Finger Key stuck in the keyhole and his foot stuck in the slot.
What Happened to the Mouse?: Usually the M.A.D. agents would be arrested at the end of each episode (at least during the first season). However, a few like Amazon Annie from "The Amazon" and the Rat from "M.A.D. Trap" are never shown being apprehended. What became of those agents is never revealed.
The film adaptation gives Gadget's hometown's name as Riverton rather than Metro City.
Why Did It Have to Be Snakes?: Putting aside the actual snake episode, Penny and Brain are afraid of ghosts, which gets the better of them when they investigate a M.A.D. base in Dracula's Castle. Penny gets over it with the help of Gadget, but Brain doesn't and stays afraid of ghosts through the whole series.
Would Hurt a Child: While she was usually just Bound and Gagged, there were at least two M.A.D. Agents who actually tried to kill Penny. The first was the Archaeologist in "All That Glitters", who tried to throw Penny off a cliff and only stopped because she pointed out that too many people would see. The second was the Clockmaker from "Coo-Coo Clock Caper", who tried to crush Penny with a mannequin wielding a mallet set to strike at 5:00.
I'll get you next time, Gadget... NEXT TIME... MMRRREEEEEEEEEEAAAAAAAOOOOOOWWWW!