This series, created by DiC, premiered in 1995, part of Bohbot Entertainment's Amazin' Adventures 2 syndicated block, and later aired on Toon Disney until around 2001. Season 2 retooled the show into an educational series entitled Gadget Boy's Adventures in History; this aired on The History Channel in 1997.
Gadget Boy & Heather contains examples of:
- Action-Hogging Opening: The intro has a lot more fast-paced action than the series does.
- Ambiguously Human: Thanks to some negative continuity, it is frequently contradicted whether Gadget Boy is a Cyborg or a robot. It is implied in the first episode that he could at least be an Artificial Human with bionics who is programmed with the original Inspector Gadget's personality.
- Anachronistic Animal: "An Ice Age Runs Through It" has Brachiosaurus, Stegosaurus, and Ichthyosaurus living in the Cretaceous period. All three were from the Jurassic.
- Animation Bump: The Adventures in History season goes through this full-stop, with some episodes having more fluid animation than others.
- Badass Adorable: On rare occasions when he's actually competent fighting the bad guys, Gadget Boy can be this.
- Belly Dancer: Some are created as part of a mirage and a couple others are shown to be real in "Valley of the Vulture".
- Breaking the Fourth Wall: Boris, Spydra's talking pet vulture frequently speaks to the audience:Spydra: My lovely cold-proof head sack keeps me immune to the uncommon cold!
Boris: (under his breath, to camera) And me immune to her ugly face!
- Butt-Monkey: Chief Stromboli. Even when Gadget Boy leaves him be, the guy can't go a minute without suffering an accident. Boris the Vulture is also one, even without Spydra abusing him all the time.
- Catchphrase: "Zowzers bowzers!" is Gadget Boy's version of the Inspector's traditional "wowzers!" catchphrase. He's also prone to quoting Maxwell Smart's "would you believe..." and "missed it by that much."
- Conjoined Eyes: In "Gadget Boy Squadron", Heather's eyes become this for a moment when she feels the vibration from the ground shaking, coming from a giant, mechanical ride controlled by Spydra's henchmen.
- Creepy Twins: Mulch and Hummus, Spydra's none-too-bright henchmen.
- Deadpan Snarker:
- Boris the Vulture constantly makes remarks about Spydra behind her back.
- Agent Heather became one in the Adventures in History season, occasionally making remarks about mistakes made by the historical figures she encounters.
- Dub Name Change: In the French dub, Agent Heather is called Estelle, Myron Dabble becomes Ronald Müller and Spydra is named Arachna.
- Evil Is Hammy: Spydra is the main villain and is extremely loud and dramatic every time she talks.
- Evil Knockoff: "Double Double Toil and Dabble" had Spydra create an evil version of Gadget Boy known as Bad Gadget Boy to frame the real deal for various crimes, but he eventually goes through a Heel–Face Turn at the end.
- Expository Theme Tune: "He gets himself out of danger with some kind of gadget Dabble made".
- Expy: Nearly all the characters are an expy of a main Inspector Gadget character: Stromboli is Chief Quimby, Heather is (an older) Penny, G9 is (a robotic) Brain, and Gadget Boy is... well, that's kinda obvious, while Spydra is a female Dr. Claw.
- Mulch and Hummus even bear somewhat of a close resemblance to some of the recurring M.A.D. agents in Inspector Gadget.
- The Faceless: Spydra. She is sometimes unmasked offscreen, (often with an effect ranging from paralysis to petrification on onlookers) but the spectator could never judge the "supreme beauty" she kept boasting. The only time she takes off her mask on-screen (gleefully lampshading it in the process), she's polymorphed into Heather.
- Goofy Print Underwear: Stromboli usually has them exposed by some means Once an Episode, usually due to something exploding.
- Hartman Hips: Heather has very large hips, as does Spydra.
- Idiot Hero: Gadget Boy means well, but he's also very gullible and dim-witted.
- Interpol Special Agent: Gadget Boy and Heather are explicitly stated to be affiliated with Interpol.
- Kid Detective: Gadget Boy is given missions to solve even though he's just a kid.
- Killer Yoyo: Gadget Boy has a yoyo in his hat that can be used as a bolas.
- Lame Rhyme Dodge: Boris would often say one after insulting Spydra under his breath, but one notable example of Boris being the one insulted occurs in the episode "Boris for President".Mulch: Just wait until Spydra catches up with you!
President!Boris: What was that?
Mulch: Er, I said, "I'll use catsup to do it!"
- Large Ham: Spydra, who often speaks in alliterative dialogue.
- Leitmotif: Spydra and Agent Heather both had their own theme music.
- Mad Scientist: Myron Dabble, creator of Gadget Boy. Okay, so he's not really mad, but hey, you've got to have a pretty odd mind to go and create a small child cyborg stuffed with hoard of crime-fighting equipment.
- Monster Mash: In the episode "Gadget-Stein", Spydra goes back to Geneva in 1816 and forces Mary Shelley to create an army of monsters that oddly all resemble Boris the Vulture. The monsters are a werewolf, a skeleton, a centaur, a fat humanoid, a cyclops satyr, a Bride of Frankenstein-esque monster, a gorilla, a mummy, a Loch Ness Monster, and even Frankenstein's Monster himself.
- Ms. Fanservice:
- Agent Heather is very attractive and curvaceous. This is especially notable in the Adventures in History season, where she frequently has her outfit changed to match the point in history they've gone to and is always quite fetching in her historical attire.
- Spydra also has a shapely body and often wore alluring outfits in the earlier episodes, even with the fact that her face is hideous enough to turn people into stone.
- Multi-Armed and Dangerous: Spydra has six arms.
- Negative Continuity: It varies in every episode whether Gadget Boy is a cyborg and G-9 is a robot, Gadget Boy is a robot and G-9 is a cyborg, or if both of them are robots or cyborgs.
- Red Eyes, Take Warning: Gadget Boy's Evil Knockoff Bad Gadget Boy from the episode "Double, Double, Toil and Dabble" had red eyes to distinguish him from the original.
- Robot Dog: G9 is a robotic dog.
- Spin-Off Babies: The series is basically about a child version of Inspector Gadget.
- Taken for Granite: Apparently the face under Spydra's mask is so terrifying, anyone who sees it will turn to stone from the shock. No, you never get to see what it looks like on screen.
- Transforming Mecha: G9 can transform into just about any tool or even vehicle the team needs.
- Unexplained Recovery: Anyone turned to stone by Spydra's ugliness is back to normal the next time they're seen, even if they're smashed to pieces.
- Vague Age: It's never clear exactly how old Gadget Boy is. He is implied to be an infant in the first episode, but occasionally seems more likely to be a ten-year-old.